Android screenshot app unrooted phone jobs

I'm in need of an Android app developer who can build an application primarily aimed at driving user engagement. This dynamic application should prominently feature the use of push notifications to keep our users connected and engaged. Skills and Experience: * Extensive experience in Android app development * Proven ability in implementing effective push notifications * Understanding of user engagement strategies within applications The aim is to build an app that not only engages the user but encourages regular active use via well-timed and strategic push notifications. The developer should also value user experience, making sure the app is intuitive and user-friendly. the app must be working based on only Python and Django

I'm looking for a skilled Android developer to build an Android app for virtual clothes try-on. I'm looking to implement a virtual try-on feature for clothing, specifically in React Native. Essential to this project is that the try-on feature should be capable of accurately recommending both size and fit of the clothing items to the user. I want target garment industries basically it's a B2B concept, right now what I want is to enable the customers to try clothes by wearing them, not actually but using a VR. Before heading forward I need to ask a question what's four plus five, if you know the answer start your proposal with it. I want you to implement something like this but on React Native Just mind the fact that the application of clothes o...

I need to extract pricing information and contact details from a Chinese website for market research and supplier contact purposes. - Extracting Contact Details: - The project also involves obtaining contact details from the website. This would typically include email addresses, phone numbers, names of suppliers, and any other relevant contact information. - It is important that this data is collected accurately and in a structured format for use in supplier outreach. Ideal Skills: - Proficiency in web scraping and data extraction. - Familiarity with Chinese websites and text. - Experience in market research and supplier sourcing. - Ability to organize data for easy analysis. - Attention to detail and accuracy in data collection. If you have experience in these areas and...

...the hunt for a proficient Android developer, who is well familiarised with Android Studio. The immediate need for my project is a Layouts Inspector tool that focuses on: - Basic Layout Structure Inspection I'm seeking out a simplistic method of inspecting the layouts to comprehend the basic structure without needing to delve into the more complex features such as component-border inspection or adjustable display parameters. This tool should develop an app solely compatible with Android smartphones. The functionality needs to integrate seamlessly into existing project work within the Android Studio environment. Ideal Skills: - Strong knowledge of Android Studio - Experience with creating tools that inspect layouts - Prior experience deve...

I am urgently in search of a seasoned Android developer to perform a minor tweak in a video feature of an app I'm working on. Currently, the app stores YouTube video IDs in Firestore. I need this altered so that it can store any video link, not just YouTube IDs. It is a task demanding a keen understanding of Android development, especially dealing with video functionalities and Firestore. Ideal Skills: - Strong experience with Android development - Knowledge of working with video functions - Experience with Firestore - Good attention to detail This is an urgent requirement and I appreciate swift, but precise work. I look forward to receiving your bids.

I'm in need of a skilled app developer who can help me fix three main problems in an existing mobile application on both iOS and Android platforms. - Scanner Quality Issue: Currently, the scanner is producing very poor quality when the black and white filter is applied. Almost the entire page blacks out, which is unacceptable. The ideal candidate should be able to diagnose and address this problem effectively. - Filter Application Speed: The current application is not only producing low-quality scans, but it's also taking a considerable amount of time to apply the filter. I need this process to be radically sped up, without compromising the quality of the final scan. - Crop - This crop features cropping both length and breadth. If we do not want to crop a pic as ...

As an individual currently working on Android Studio, I require a seasoned Android Studio developer. The tasks include, but are not limited to: - Assisting with project completion - Fixing prevalent bugs - Incorporating a simple, aesthetically pleasing UI design This project places great emphasis on Android Studio, thus expert knowledge and experience in this field are necessary. Key features of the project include: - User login/authentication - Database integration - Push notifications I am looking for a developer with a keen eye for detail, along with substantial experience in developing reliable, high-quality Android applications. Your portfolio should demonstrate a strong and diverse range of past projects.

I'm urgently looking for a web scraping expert who can help me gather information from various medical service provider websites. Key Requirements: - Extract doctor names, contact information, medical service details, and additional data such as phone numbers, specialties, and participating plans. - The information should be pulled from three specific websites - Website 1, Website 2, and Website 3. Your deliverable: - The scraped data should be compiled into a CSV format for easy analysis and integration into our system. Ideal Skills: - Proficient in web scraping and data extraction - Advanced knowledge in handling and exporting data formats like CSV - Experience in scraping medical websites or similar domains would be a plus. Please bid only if you can start immediatel...

Confirmis ( ) is a Singapore-based business information provider specializing in connecting businesses with ...building operators, etc. • Take pictures of the candidate’s residential address, as per Confirmis’ standard operating guidelines. • Provide observation about the address such as the location, the building, etc • Job will only take less than one hour to accomplish (excluding travel time) REQUIREMENTS: • Must be living in (or nearby) Jianguo Rd., Xindian Dist., New Taipei City • Has a camera or phone/tablet of quality with a camera, internet access • Available between business hours to visit Note: Payment will be released the following week after the site visit to give us time to organize the report and contact you if we need additi...

I need an experienced freelancer capable of creating and implementing a mobile push notification system, particularly for both iOS and Android. I have a Health Care cross platform mobile app ready to launch and I need Notifications done by using cross platform system like Cordova and/or Angular. Key Responsibilities: • Handle the execution of informative alerts, real-time updates, status updates, and reminders. • The system should be designed to send notifications upon the completion of services and at defined specific times or events. Ideal Skills and Experience: • Demonstrable experience building notification systems for both iOS and Android. • Complete understanding of programming rules and regulations for each specific platform. • An inno...

We are looking for a QA tester capable of identifying error between expected and actual travel times on maps. This is just a quick job for investigating the root cause of timing inconsistencies. Please have a quick look to our android app in playstore - no need for any account or registration Thanks

I'm looking to improve my app tracking capabilities with a focus on measuring downloads, analyzing revenue, optimizing ads, and discovering new opportunities. I'm in need of an expert in AppsFlyer and Google Analytics 4 (GA4) to ensure both iOS and Android versions of my app are correctly set up to achieve these goals. Key Responsibilities: - Audit and optimize AppsFlyer and Google Analytics 4 for my app. - Analyse user engagement data to advise on app improvement. - Monitor and analyze app revenue and recommend revenue-boosting strategies. - Track and optimize Ads performance. - Unearth opportunities from our app tracking data. Desired Skills: - Proficient in AppsFlyer and Google Analytics 4. - Experience in apps trac...

I am seeking an Android app developer experienced in creating calendar apps. My ideal freelancer will be able to: - Implement reminder notifications. This is a key feature of the app that will need to be developed with an option for the user to customize the time of notification. - Ensure synchronization with Android's native calendar app is seamless with the reminder notifications. - Develop an effective Task Management system within the app. - Provide a weekly view option for users to navigate their schedule. Desirable skills: Android Development, Java, UI Design, and Database Management. Previous experience creating or working with calendar apps would be advantageous.

I'm looking for a highly experienced Flutter developer to integrate Bluetooth Low Energy (BLE) scanning and WiFi configurations into a cross-platform mobile application. Requirements: - Cross-platform compatibility: The application should operate seamlessly on both Android and iOS. - BLE Functionality: The app should be able to scan for and connect to BLE devices, prioritizing a specific custom BLE device. - WiFi Configurations: The developer should also build functionalities that will enable the app to connect and configure WiFi. Ideal Skills and Experiences: - An expert level of knowledge and practical experience with the Flutter framework is critical for this role. - A deep understanding of utilizing BLE technologies, particularly with custom BLE devi...

Confirmis ( ) is a Singapore-based business information provider specializing in connecting businesses with global capabilities; comprised of indu...community, police stations, building operators, etc. • Take pictures of the candidate’s residential address, as per Confirmis’ standard operating guidelines. • Provide observation about the address such as the location, the building, etc • Job will only take less than one hour to accomplish (excluding travel time) REQUIREMENTS: • Must be living in (or nearby) Pangasinan, Philippines • Has a camera or phone/tablet of quality with a camera, internet access Note: Payment will be released the following week after the site visit to give us time to organize the report and contact you if we need additiona...

I'm in need of a skilled game developer or team to digitalize my board game for both iOS and Android platforms. The game's primary target audience is teenagers, so it must be appealing and engaging for this age group. Key requirements: - Mobile platform: The game must be available on iOS and Android, ensuring its accessibility to a wide audience of teenagers. - Multiplayer functionality: This is a crucial feature of the game. It should enable teenagers to play the board game with friends in a digital environment. This will enhance the social aspect of the game, making it more enjoyable for its target audience. - Full game development: The developer or team should be able to handle all aspects of game development, including coding, design, and graphic creation. This...

We are looking for some small animations to be used to highlight the various stages a print job will go through when submitted to our system. We would like these animations to make use of our logo and to highlight the following stages: 1. Upload the print job 2. Compress the print job 3. Analyse the ...stages a print job will go through when submitted to our system. We would like these animations to make use of our logo and to highlight the following stages: 1. Upload the print job 2. Compress the print job 3. Analyse the print job (count colour and mono pages) 4. Encrypt the print job The animations will be separate files and we will then use them in our application. I have included a screenshot showing where the animations will be used on our print ticket, as well as our com...

I'm looking for a remote freelancer who can help me set appointments with Shopify sellers who are interested in utilizing our AI technology to boost their conversion rate. Ideal Skills and Experience: - Proficient in Email Outreach, Phone Calls, and Social Media Messaging - Prior experience with appointment setting, especially in the eCommerce sector - Strong communication and negotiation skills - Understanding of AI technologies like recommendation engines and personalization engines Key Responsibilities: - Engage with Shopify sellers via email, phone calls, and social media to introduce our AI technology - Schedule appointments with those who express interest in utilizing the technology - Maintain a high level of professionalism and enthusiasm throughout the appointm...

My old Android slot machine app is proving incompatible with the latest version of Android Studio. Despite having imported the necessary Android package in the project, I'm unable to build the app. I keep encountering an error message stating "java: package does not exist". Here's what I need: - Identify the source of the build failure - Fix the "java: package does not exist", making sure the app builds successfully - Verification that the app is working perfectly in the current Android Studio version The ideal freelancer for this job would have extensive experience with Android Studio, and debugging skills for identifying and solving build problems. Knowledge with Java and past experience ...

I need an expert Android app developer to turn my already-designed flowchart into a fully functioning application. Please Read the attachment. My budget is not more than 40000 INR

We are seeking a talented and experienced Java/Kotlin Developer to join our development team. The ideal candidate should be proficient in software development principles and practices. In this role, you will work on a variety of projects, from developing new...software development principles and practices. In this role, you will work on a variety of projects, from developing new features to maintaining and enhancing existing applications and creating Unit Tests. Key Requirements: - The application must be compatible with Android and iOS - I'm aiming for a high level of testing coverage, specifically continuous integration tests that run with every code update. Please bid with relevant examples of your work and an outline of how you would approach the testing of a Kotlin-bas...

Attached I have added an example of what I want the business card to look like. I have the : Images, verbiage, logo and all info I need added My colors black, yellow and gray/ white Tagline: “We specialize in unleashing your brands true potential” Instagram: Studio_88_in Email: info@st Phone: (404)268-4

I require a compilation of 1,000 genuine, individual leads for users of Ethereum wallets located primarily in North America. These leads will strategically ai...request, freelancers bidding on this project should possess: Key Requirements: - Superior lead generation capabilities - Solid understanding of the crypto and digital wallet market, specifically Ethereum - Demonstrated experience in targeting and acquiring leads within North America Target Audience: - Ethereum Wallet Users - Geographical Focus: North America Each lead should come with associated phone numbers for cold calling purposes. Previous experience in crypto lead generation in North America will be highly beneficial. Your skills in detailed and accurate lead data collection will be essential to the success of thi...

I am seeking researchers in Pietermartizburg, South Africa to conduct market research for a retail audit. The ideal candidate should have good communication skills. You will have to own an android mobile device to be eligible for this project. You will visit 3 supermarkets in the city of Pietermartizburg and the payment for this project is €150 Specific requirements for the project include: - Conducting a retail audit in Pietermartizburg, South Africa - Uploading data on our app - Android Device is required Skills and experience needed for this project: - Strong analytical skills - Excellent communication skills - Ability to finish the project by a specific deadline -Flexible schedule Please get in contact if you are interested in this project.

...and a corresponding mobile app, where users can take a photo of the red scratches on the package and convert the red intensity into the applied pressure values. Below we explain these steps. 1. Users scan the red scratch by taking a photo with a mobile. 2. The app separates the photo into R, G, B images. 3. The app only uses R channel (discard the rest). The app detects the starched line from the R channel image and extract the average value of the red intensity on the scratched line. The app also detects the red intensity on the background. The app calculates Rstratch – Rbackground = dR. 4. We have a calibration equation (Pressure = dR x alpha). Based on the calibration equation, the app converts the average red intensity to t...

I need someone on a daily basis to help me streamli...attending meetings, and managing assorted tasks virtually. Ideal skills and experience would be: - Expert organizational and time-management skills - Effective and professional written and oral communication - Familiarity with standard business software such as Microsoft Office - Available daily with a flexible schedule - Proficient in English Preferred Communication Tools: - Email - Phone - Messaging app Please note: My immediate time zone isn't a determining factor for this role, yet availability in accordance with a standard North American business day is advantageous. If you are a disciplined, results-oriented professional able to work independently with minimal supervision - I'm looking forward to...

I'm looking for a skilled Android app developer who specifically specializes in gaming apps, particularly those of the puzzle genre. Key requirements include: - Designing the game itself, implementing engaging and challenging puzzles. - Developing the app in line with the design, ensuring a smooth user experience. - Submitting the completed app to Google's Play Store once finalized. Ideal Skills and Experience: - Must have experience in both game design and development, particularly with puzzle games. - Proven track record in releasing Android apps. - Strong understanding of Google's submission process. This project will require a balance between creative design, logical programming, and a knowledge of the Android ecosystem. P...

...plugin to version 5 and introduce Android compatibility. I am looking for a Geofence plugin. I have a good starting point with a public plugin, but it needs updating. Here is the source repository: Please reference it, and add updates to it for capacitor version 5, update any of the swift or Objective C code that may be out of date, add corresponding support for Android. Key Requirements: - The main focus of this project is to enhance the plugin's compatibility with various platforms, particularly iOS and Android. - The plugin should be updated to Capacitorjs v5 to ensure it's leveraging the latest features and security patches.. Ideal Skills and Experience: - Proficient in Capacitorjs, IOS and Android development. - Experience in updating

The task is to fix the CSS for the following pages to make it responsible. The designs have been done for a large (4K) monitor and need to work for all page sizes down to a mobile phone. * * (shares most of the CSS of the home page) * * Please test the pages in your browser to estimate the work to be done. PROPOSALS POSTED LESS THAN 1 HOUR AFTER THE PUBLISHING OF THIS PROJECT WILL BE IGNORED. The blog is based on Jekyll with Sass/SCSS. The CSS code is rather complex, and it has a grid layout. It is hosted on GitHub. You will get access to the repo.

...authorized representative, such as line of business, key executives' name, etc. • Take pictures of the subject company and its vicinity, as per Confirmis’ standard operating guidelines. • Provide observation about the company to gauge activeness, e.g., staff working at the premise, loading/unloading of goods, etc. REQUIREMENTS: • Must be living in (or nearby) Mevo Dotan, Israel • Has a camera or phone/tablet of quality with a camera, internet access • Must be available during business hours (9 AM - 4 PM) on working days Please see the attached file for the site visit guideline. You are only required to deliver the pictures, video & observations and are not expected to put together a report like the Sample Report. Note: Milestone ...

I'm looking for an experienced mobile app developer who can create a functional Android app that emphasizes a user registration and login system. This project centers around creating a user-friendly system that makes registering and logging in seamless for the user. Key Requirements: - Expertise in Android app development. - Can design a user-friendly interface. - Has experience in developing secure user registration and login systems. - Familiarity with relevant protocols and standards for user data security. - Excellent troubleshooting and communication skills. If you can demonstrate previous work with similar Android apps, your application will stand out. I look forward to seeing your proposals.

אני מחפש מפתח אפליקציות אנדרואיד מיומן ליצירת פלטפורמת חנות אפליקציות אנדרואיד בקנה מידה קטן. המטרה העיקרית של פלטפורמה זו היא לספק למשתמשים גישה למבחר של כ-10 יישומים להורדה. יש לפתח את האפליקציה בשפת JAVA בלבד. יש לספק לי את קוד המקור לשימוש אישי ולשינויים עתידיים. תכונות עיקריות: 1. מערכת רישום ואימות: • המשתמשים יידרשו להירשם באמצעות שמם המלא וכתובת האימייל שלהם בלבד. • האימות יתבסס על סיסמה חד פעמית (OTP) שנשלחה לכתובת הדוא"ל שסופקה על ידי המשתמש. • יושמו מנגנוני אימות חזקים כדי להגן מפני ניסיונות מעקפים והזרקות זדוניות. 2. מנוי שנתי: • תהליך ההרשמה יכלול תשלום באמצעות כרטיס VISA עבור מנוי שנתי. • תוקף המנוי יהיה לשנה ממועד הרכישה. 3. פונקציונליות נוספת: • למשתמשים עם מנוי פעיל תהיה אפשרות להוריד אפליקציות מהחנות לאחר אימות מוצלח. ...

...front end and prototype of my crypto Wallet and NGO app I am seeking an experienced freelancer capable of developing a front-end prototype for a crypto wallet app. Below are the main requirements for this project: - Android OS compatible: The app needs to be designed specifically for Android users. - Functionalities: The app should be able to track cryptocurrency prices, store various types of cryptocurrencies, and incorporate security features such as two-factor authentication. - Cryptocurrency Support: The app should particularly be able to support BSC (Binance Smart Chain) cryptocurrency. Ideal candidate would have experience in Android development, cryptocurrency applications, and a strong understanding of security feature...

I need assistance in researching and creating a database/list of potential customers in the hair salon industry. This project involves: - Comprehensive business analysis - Gathering customer demographics Key aspects for the potential customer list: - Salon name - Contact person / Owner Name - Phone number - Email address - Website homepage - Website contact form address - Physical Address - Number of stylists / employees List should be 10,000+ records Ideal candidate should have excellent research skills and proficiency in creating detailed spreadsheets. Fusion of data analytics skills with practical business insight would be a winner for this project. Please mention that you are a data wizard in your proposal so I will know you have read this description.

Add below features onto the apk of custodial crypto wallet when users take actions in transaction. 1. mobile phone number authentication 2. Microsoft and Google Authenticator authentication 3. e-mail authentication

I am looking for a WordPress expert who can optimize the loading speed of my website. The website is currently taking more than 10 seconds to load. - Hosting: The website is currently hosted on a VPS. I would appreciate a thorough analysis to identify solutions. - Familiarity with tools such as GTmetrix, Google PageSpeed Insights, or similar; - it must be ok on mobile and desktop... check screenshot on how would look, if possible = Budget: US$30.- dollars... NOTE: freelancer must have at least 10 positive feedbacks. Payment in 2 parts, 2nd part only after website speed is ok (important); Happy Bidding

I'm looking for someone who is smart and can record some action songs for preschool kids. No previous experience is required. You can just use your phone camera to record the videos. You only have to act/dance based on the songs we provide. You will get the payments for each video song you record. We will provide you with all the reference songs for each video. It's just 3-5 minute long videos and it depends on the song. Please take a look at the example video (This is just a demo video and the rhymes will be mostly in English.) ============ ============ ============ ==== ============ ============ ============ ====

I am looking for an expert mobile app developer with experience in AI and video chatbot development to create a Conversational AI Video Chatbot App for Android and IOS. The core functionality of the app is to provide real-time interaction between users and an AI agent through video and voice chat. The chatbot serves as an interviewer, interacting with candidates for HR and technical interviews. I will provide training and prompts for the chatbot, including testing its functionality. One aspect involves conducting real-time interviews, managing calendars, and scheduling appointments. Additionally, the AI will engage in video calls, displaying a face and conversing in real-time. Candidates are required to fill out a form related to the job role one to two hours be...

...for an iOS and Android app. WITH ATLEAST 5+ YEARS OF WORKING WITH REACT NATIVE Key Features: - User login/authentication - Push notifications - Rsocket - Optimized for both mobile and tablet with 2 different designs - SQLlite for local DB Design Requirements: - Minimalistic, yet bold and vibrant design - Custom illustrations to enhance user experience Preferred Third-Party Integrations: - Google Maps - Social media platforms - Payment gateways Ideal candidates should have: - Proficiency in React Native - A strong understanding of user interface and design principles - Experience in integrating third-party services - Excellent communication skills and a proactive approach. If you possess these skills and are confident in delivering a high-quality, feature-rich ...

...correctly if the code is run outside the container. I’ve developed a simple Mongo connection js file which tests this. The output is shown here - Also, here is a screenshot of a sample GET call to the API endpoint using Postman. This call works when the Mongo library is commented out in the file. I’ve also checked the Mongo library is present within the running Docker container. This has been done by looking at the file system of the Node app within Docker Desktop. NOTE - I have deleted the node_modules folder to reduce the size of the sample application for upload. The Docker compose process should rebuild

I just need your help to complete 10 simple surveys for me that won't take very long. Fill out on desktop or computer. Please simply fill out everything and send me the screenshot of surveys finish that. That's all.

Hi This i Somansh from Feedx Food. We work in F&B business. We are looking for 3D design layout for our food outlets Can we connect over chat/ phone call to discuss the same

...create compelling App Store screenshots for my app. This is a dual-platform app for both iOS and Android and I'm looking for an expert who has experience designing for both platforms. Note design of the app is already done, you just need to generate and design the screen shots. Key Requirements: - Design of 4-6 screenshots for the app - Highlighting of key features such as user interface, functionality, and unique selling points - Expertise in Sketch to ensure high-quality designs compatible with App Store requirements for both iOS and Android This project is perfect for someone who's creative, has an eye for design, and understands the unique requirements for App Store screenshots. A strong portfolio of previou...

I'm looking for a skilled professional to boost the current performance of my AdWords campaign. Our focus is to enhance overall return, particularly by decreasing the cost per click. Key objectives: - Improve Ad Copy: Crafting compelling, engaging ad copy that drives clicks - Targ...right audience - Landing Page Optimization: Ensuring the landing pages are enticing and aligned with our ad content Ideally, the selected freelancer should have: - Proven expertise in Google AdWords - Strong analytical skills - Experience in A/B Testing - Understanding of conversion tracking (especially phone calls) - Creative copywriting skills Your primary goal would be to increase the campaign's overall ROI by reducing the cost per click, while maintaining or increasing the number of ...

I'm in need of a seasoned developer to build an OS/Android application that's applicable to mobile devices, tablets and company laptops. The main aim of the app is to facilitate the shift from manual logbook entries to a digital interface. Key Features: - Digital logbook functionality to create, view, edit and sort entries - User authentication and authorization capabilities - Data synchronization with cloud storage for easy access and backup purposes Your expertise in software development with proficiency in user interface design and cloud synchronization is necessary for this project. Prior experience in creating logbook applications or related software platforms will definitely be a plus. Be prepared to show relevant examples of your work and explain how they ...

I'm seeking for an web developer who can optimize the mobile responsiveness of my single page website specifically for Android devices. Key requirements: - Adjust the text content to scale properly, currently it doesn't. - Make sure images resize appropriately, right now they are not fitting properly. Skills and experience: - Profound knowledge in mobile responsive design - Capable of handling both Android and web-based projects - Skilled in optimizing navigation menu for mobile devices.

I'm in need of a QA specialist in America to conduct manual testing on my Android app. Here's what you need to know: - **Purpose**: The primary aim is to ensure the app's functionality and performance under various scenarios. - **Features**: The app should include login and registration functionalities. Your task will be to verify these features work as intended. - **Devices**: The app needs to be tested specifically on smartphones. Overall, I'm looking for someone who can systematically explore the app, identify potential issues, and provide detailed feedback on their findings. Experience with testing Android apps is essential. Strong communication skills are also important, as clear and concise reporting will be crucial.

I am in need of a skilled software developer with superior expertise in Android mobile app development. The operating system I am interested in is Android and the software to be developed is a mobile application. However, the main function of the mobile app is yet to be defined, but this shall be communicated clearly once a freelancer is selected. Ideal Skills: - Android Development - Java - Kotlin - UX/UI Design Experience: - Proven experience in mobile app development - Portfolio of released applications on the App store or the Android market - Solid experience in mobile app development life cycle.

I am seeking researchers in Durban, South Africa to conduct market research for a retail audit. The ideal candidate should have good communication skills. You will have to own an android mobile device to be eligible for this project. You will visit 8 supermarkets in the city of Durban and the payment for this project is €280 Specific requirements for the project include: - Conducting a retail audit in Durban, South Africa - Uploading data on our app - Android Device is required Skills and experience needed for this project: - Strong analytical skills - Excellent communication skills - Ability to finish the project by a specific deadline -Flexible schedule Please get in contact if you are interested in this project.

I am seeking an experienced Android developer - Kotlin for app development.