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I have an existing mobile app project called CAPTION MASTER . The app is already designed in Figma and the mobile app code is partially ready. The project stopped before completing the backend, API integration, subscriptions, and final deployment. The app is built for iOS and Android and is focused on short video captioning and translation. Figma design is ready: [login to view URL]:1&locale=en&type=design I will provide the existing project files, including: * Flutter mobile app project * Existing backend project * Figma design * Logo and design assets if needed App Idea CAPTION MASTER is a mobile app that allows users to: * Import a video from their device * Generate automatic captions/subtitles * Translate captions into another language * Edit caption text * Choose caption style, font, color, and position * Preview the video with captions * Export the final video with burned-in captions * Export subtitle files such as SRT if possible * Save projects/drafts * Access premium features through subscription The target users are content creators for TikTok, Instagram Reels, YouTube Shorts, and social media videos. Current Situation The design is ready and the frontend is partially developed, but I need a professional developer to complete the technical side. The missing or incomplete parts are: 1. Backend completion 2. API integration 3. Video upload and processing 4. Speech-to-text / transcription 5. Caption translation 6. Subtitle generation 7. Burn captions into video 8. Subscription system 9. User authentication if needed 10. Testing on iOS and Android 11. App Store / Google Play readiness Existing Backend There is an existing backend project using Python/Flask. It appears to use: * FFmpeg * Faster Whisper / Whisper-based transcription * Translation service * Video/audio processing * SRT subtitle generation I need the developer to review the current backend and decide whether to continue using it, improve it, or rebuild the backend in a better production-ready way. Required Work I need you to complete the full app workflow: 1. Review Existing Code * Review the Flutter app code * Review the backend code * Review the Figma design * Identify what is already working and what is missing * Provide a clear plan before implementation 2. Backend Development * Complete or rebuild the backend * Create stable API endpoints for the mobile app * Handle video uploads securely * Process video/audio using FFmpeg * Generate captions using Whisper or another reliable speech-to-text API * Translate captions into selected languages * Return captions, SRT files, and processed video * Add proper error handling * Add logging * Make the backend ready for production deployment 3. API Integration * Connect the Flutter app to the backend * Make the upload, caption generation, translation, preview, and export flow work properly * Add loading states, progress states, and error messages * Make sure the app works smoothly with real videos 4. Subscriptions / Payments Please add a subscription system for iOS and Android. Preferred solution: * RevenueCat integration or * Native Apple In-App Purchase and Google Play Billing Subscription requirements: * Monthly plan * Yearly plan * Free user limitations * Premium access control * Restore purchases * Subscription status check * Lock premium features behind subscription 5. Firebase / Authentication If needed, complete Firebase setup for: * User login * Anonymous login or email login * Saving user projects * Tracking premium status if required If Firebase is already included in the project, please review and fix the setup. 6. Video Export The app must be able to: * Export final video with captions burned into the video * Save/export video to the user’s device * Export subtitle file if possible * Keep good quality after export 7. Testing Please test the app on: * iPhone / iOS simulator and preferably real iPhone * Android emulator and preferably real Android device Testing should include: * Upload video * Generate captions * Translate captions * Edit captions * Change caption style * Export video * Subscription purchase flow * Restore purchase * Error handling 8. Deployment Support I need help preparing the app for: * Apple App Store * Google Play Store Including: * Build configuration * Bundle ID / package name review * App signing guidance * Production backend URL setup * Environment variables * Final testing build * TestFlight / internal testing if possible Important Requirements * The app must match the Figma design as closely as possible. * The app must support both iOS and Android. * The final code must be clean and organized. * The backend must be secure and production-ready. * API keys must not be exposed inside the mobile app. * The app should be scalable and not just a local demo. * The developer must explain what server/cloud hosting is needed. * The developer must provide setup instructions after completion. Preferred Tech Current mobile app appears to be Flutter. Backend currently appears to be Python/Flask. I am open to suggestions if you recommend a better backend approach, but please explain why. Possible services: * OpenAI Whisper API * Faster Whisper * AssemblyAI * Deepgram * Google Cloud Speech * OpenAI API for translation if suitable * RevenueCat for subscriptions * Firebase if needed * AWS / Google Cloud / Render / Railway / DigitalOcean / VPS for hosting Deliverables At the end of the project, I expect: 1. Fully working Flutter iOS/Android app 2. Completed backend 3. API fully connected to the app 4. Subscription system working 5. Video captioning and translation workflow working 6. Video export working 7. Clean source code 8. Deployment instructions 9. Environment variable documentation 10. TestFlight / Android test build support 11. Clear explanation of how to run the app locally and in production
Project ID: 40456192
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79 freelancers are bidding on average $203 USD for this job

Hello, CAPTION MASTER is a strong product idea, and I can help complete it into a production-ready iOS/Android app. I have 11+ years of experience in Flutter, AI integrations, video processing, backend systems, and subscription-based mobile apps. I can: • Review and complete the existing Flutter + Flask codebase • Integrate Whisper/Faster-Whisper, FFmpeg, translation APIs, and subtitle workflows • Build stable production-ready APIs with secure upload/processing pipelines • Implement RevenueCat subscriptions (monthly/yearly + restore purchases) • Complete Firebase/authentication setup if needed • Optimize export flow for burned captions + SRT generation • Prepare the app for App Store & Google Play deployment I’ll first audit the existing codebase and provide a clear implementation roadmap before development begins. The final delivery will include clean source code, deployment setup, environment documentation, and testing support for both iOS and Android. Looking forward to discussing the current project files and next steps. Best regards.
$140 USD in 7 days
8.4
8.4

This looks like a great fit, I will review your existing Flutter and Flask code, complete the backend — video processing with FFmpeg, Whisper-based transcription, caption translation — wire up the API to the app, integrate RevenueCat for subscriptions, and prepare builds for both stores. For transcription, I will benchmark Faster Whisper against the OpenAI Whisper API on your typical video lengths to find the right balance of speed, accuracy, and hosting cost before committing to either. Questions: 1) What languages do you need caption translation to support at launch? 2) Do you have a hosting budget preference — managed (Railway/Render) or a VPS? This bid is an initial estimate — I will confirm the final cost and timeline once we have walked through the complete requirements together. Looking forward to talking through the details. Kamran
$90 USD in 5 days
7.4
7.4

A Warm Hello! I carefully reviewed the CAPTION MASTER requirements, and this is a strong production-level AI video processing app rather than a simple Flutter project. Since the Figma design and partial codebase already exist, the most important part now is stabilizing the architecture, completing the backend pipeline, and ensuring smooth video processing on real devices. We can help by: Reviewing the current Flutter + Flask codebase Auditing what is reusable vs what should be rebuilt Completing the backend APIs and processing pipeline Integrating Whisper/Faster-Whisper for transcription Adding translation, SRT generation, and FFmpeg caption burn workflows Implementing RevenueCat subscriptions for iOS/Android Completing Firebase/auth/project storage if required Preparing production-ready deployment and App Store submissions Recommended architecture: Flutter frontend Python FastAPI backend (better async/scalability than Flask if upgrade is needed) FFmpeg worker pipeline for rendering/export Whisper/Faster-Whisper or Deepgram based on speed/cost goals Firebase/Auth + Cloud Storage RevenueCat for cross-platform subscription handling AWS/GCP for scalable processing infrastructure We also understand the critical areas: Secure API key handling Queue-based video processing Export quality optimization Real-time progress states Error recovery and logging App Store compliance for subscriptions and media processing apps Best Regards, Jemin Sagar
$140 USD in 7 days
7.1
7.1

With over a decade of experience in Web and Mobile Development, I am confident that I can help you successfully complete your CAPTION MASTER project. My team at Carol Data Technology comprises of skilled professionals, just like myself, with expertise in JavaScript, PHP, Android and notably, Flutter - the language used to develop your mobile app. When it comes to the specific requirements of your project, I bring valuable experience in backend development and API integration. Having worked extensively with languages like Python and frameworks like Flask, I am certain I can elegantly review your existing codebase and either improve or rebuild the backend, as needed. Additionally, my proficiency in using FFmpeg for video processing will prove invaluable for crucial functions like caption generation and burnt-in subtitles. In keeping with your requirement for a subscription system, I would recommend integrating RevenueCat or facilitating Native Apple In-App Purchase and Google Play Billing. My prior work on similar payment systems guarantees a secure setup that includes monthly/yearly plan structures and appropriate access control to lock premium features. A professional user authentication system through Firebase is also well within my capabilities. Alongside providing exceptional technical competency, I aim for transparent communication throughout the project and an unwavering commitment to delivering on time.
$140 USD in 7 days
6.9
6.9

Hi, I’m a full-stack mobile developer with 10+ years of experience building and completing production-ready mobile applications using Flutter, Python, Node.js, AI integrations, subscriptions, and cloud-based media processing. My approach would start with a structured audit of the Flutter app, Flask backend, current APIs, and processing pipeline to identify reusable components and define the fastest production path. If the existing backend architecture is solid, I’d optimize and extend it; otherwise, I’d recommend a cleaner deployment-ready structure. I can complete video upload/processing, Whisper-based transcription, translation workflow, SRT generation, caption rendering, RevenueCat subscriptions, Firebase integration if needed, export handling, testing, and App Store / Play Store readiness. Clean code, environment documentation, deployment guidance, and full handover are included. Best regards
$170 USD in 7 days
7.0
7.0

Hi there, I see you're looking to develop CAPTION MASTER, which already has a design in Figma. It's great that you have a clear vision for the app. With around 10 years of experience in mobile development and working with Flutter, I can help bring your app to life. I understand you want a user-friendly video captioning tool, integrating translation features effectively. I have built similar apps, including a regional tutoring platform, an internal CRM for a property agency, and a React Native field-reporting app. Let’s connect and discuss how we can make CAPTION MASTER a success. Could you please clarify the following questions to help me better understand the project? Q1: What specific video processing features do you want to implement in the app? Q2: Are there any particular translation services or APIs you prefer to use? Q3: What are the main platforms you want to prioritize for the app launch—iOS, Android, or both?
$200 USD in 4 days
6.6
6.6

Hi there! I have extensive experience in developing similar video captioning apps like CAPTION MASTER. I can seamlessly integrate the backend, APIs, and subscription system for iOS and Android. My approach involves thorough code review, backend enhancement, API integration, and seamless deployment support. Let's discuss how I can bring your project to life with clean, organized code and precise adherence to the Figma design. Looking forward to collaborating on this exciting project!
$180 USD in 3 days
6.4
6.4

Hello, I read your CAPTION MASTER project and I’m confident I can finish the backend and app to production. I will align the Flutter frontend with a robust Python/Flask backend, FFmpeg processing, and Whisper-based transcription to deliver reliable captions and translations. My plan includes reviewing current code, implementing stable APIs, secure uploads, subscription with RevenueCat or in‑app purchases, and complete iOS/Android deployment. I can start with a phased plan and deliver a production-ready MVP within a few weeks, with full testing and deployment guidance Best regards,
$155 USD in 14 days
5.8
5.8

Hi I will develop a high-performance Flutter mobile application for video captioning, featuring seamless video importing, precise automated or manual text synchronization, and an intuitive UI optimized for smooth editing and exporting. Tejal
$250 USD in 7 days
6.0
6.0

Hi, A partially built Flutter app with a Flask backend, Whisper transcription, FFmpeg processing, and a Figma design waiting to be matched. The missing pieces: stable API endpoints, video upload handling, caption translation, subscription integration, and a working export flow. I'll take what exists and complete it. First, I'll review your Flutter code, Flask backend, and Figma design - documenting what works and what needs rebuilding. Then I'll create or complete the backend API (Python/Flask or migrate to FastAPI for better performance) handling secure video uploads, FFmpeg processing, Whisper-based transcription, caption translation, SRT generation, and burned-in caption export. The Flutter app will connect to these endpoints with proper loading states, progress indicators, and error handling. RevenueCat handles subscriptions (monthly/yearly plans, free user limits, premium feature locking, restore purchases) across iOS and Android. Firebase adds authentication (anonymous or email login) and project saving. The final video export preserves quality while burning captions. Testing covers both platforms - real devices if possible. Deployment support for App Store and Google Play, including build configuration, signing guidance, and production backend setup. Here's an extra: a caption style preview system - users see changes to font, color, and position in real time before processing the full video, saving server load and wait time.
$30 USD in 2 days
5.7
5.7

Hello Dear! Greetings from Toriqul Global Solutions! We are a reliable and experienced web design & development company led by Engineer Toriqul Islam (B.Sc. in CSE, RUET), with over 10 years of proven industry experience delivering quality digital solutions. At Toriqul Global Solutions, we build modern, user-friendly, high-performance websites focused on simplicity, elegance, and functionality to boost engagement and business growth. Technologies We Use: Custom Websites Development Using ======>Full Stack Development. 1. HTML5 2. CSS3 3. Bootstrap 4. jQuery 5. JavaScript 6. AngularJS 7. React JS 8. Node.js 9. WordPress 10. PHP 11. Ruby on Rails 12. MYSQL 13. Laravel 14. .NET 15. CodeIgniter 16. React Native 17. SQL / MySQL 18. Mobile app development 19. Python 20. MongoDB and more skills What will you get? • Responsive design on All Devices •Reusable components •Clean code •Timely delivery tested •Clear communication We would be honored to discuss your project requirements and help bring your ideas to life. Thank you for your time and consideration. Warm Regards, Toriqul Global Solutions
$50 USD in 3 days
5.4
5.4

With almost half a decade of experience in Full Stack Development, with expertise in Flutter and React Native, I'm certain I am the right developer to complete your CAPTION MASTER app. My proficiency extends not only to mobile development but also web development, backend systems and database management perfect for handling the current missing components in your app. Notable among my skills that align perfectly with your project are my experience deploying over 30 mobile applications and implementing complex UI/UX designs. This allows me to not only contribute to the API Integration and Backend Development, but also the design implementation which will ensure smooth integration of the frontend and backend functionalities. My past clients have applauded my ability to build scalable systems seamlessly integrated across platforms, resulting in positive user engagements. Additionally, I am familiar with revenue generation strategies required as evidenced by my successful integrations of payment plans
$140 USD in 7 days
6.3
6.3

Hello! As per your project post, you’re looking to complete and productionize CAPTION MASTER, a short-video captioning and translation app for iOS and Android. The goal is to transform the existing partially completed Flutter and Python/Flask setup into a fully functional, scalable, and subscription-ready product for content creators using TikTok, Instagram Reels, and YouTube Shorts. My focus will be on completing the entire app workflow including: reviewing the existing Flutter app, backend, and Figma design system, finalizing the upload-to-export video pipeline, integrating automatic transcription and multilingual caption translation, enabling editable caption styling (fonts, colors, placement), supporting video previews with burned-in captions, subtitle exports (SRT), project saving/drafts, and implementing a stable subscription system with premium feature access control. I have experience working on AI-powered media applications, video processing workflows, subtitle generation systems, mobile subscription architectures, and scalable creator-focused platforms. My focus will be on turning CAPTION MASTER into a polished production-ready app with stable backend infrastructure, smooth user experience, and reliable export performance across devices. Let’s connect to review the existing codebase, backend architecture, and current development status so we can define the cleanest path toward launch-ready completion. Best regards, Nikita Gupta.
$400 USD in 22 days
5.4
5.4

Hi, Your project is more than a Flutter app completion — it’s a full AI-powered captioning and video processing platform that needs stable backend workflows, smooth mobile UX, and production-ready scalability. I can help you complete: Flutter app integration with backend APIs Whisper/FFmpeg caption generation workflow Translation + subtitle export (SRT) Video rendering with burned captions RevenueCat/native subscriptions Firebase/auth setup if needed iOS & Android testing + store readiness I’d recommend keeping Python for the video/AI pipeline since FFmpeg + Whisper workflows are already well-suited for Flask/Python, but restructuring it for production stability, queue handling, and secure API architecture. I’ve worked on Flutter apps, API-driven platforms, subscription systems, and media-processing workflows focused on scalability and smooth UX. ✔ Phase-based execution (audit → backend → integration → deployment) ✔ Initial codebase review + implementation roadmap within first few days ✔ Production-ready backend and secure API handling Share repository access and backend status, and I can review the current architecture and propose the best production-ready execution plan immediately. Regards Abhishek
$140 USD in 7 days
5.5
5.5

As an experienced full-stack developer with a strong background in mobile app development, I am confident that I can complete your CAPTION MASTER project successfully. Before diving into the code, it is crucial to review the current state of the app, which includes assessing the Flutter and backend codes, along with the Figma design. This will enable me to draft a clear plan that addresses what's already functional and what needs improvement. Given my skill set that includes expertise in Android, Flutter, and iOS Development, I understand the intricacies of creating stable API endpoints for the mobile app and handling secure video uploads. Additionally, I have experience of working with FFmpeg and relevant transcription tools like Faster Whisper as required by your existing backend setup. Hence, I can efficiently process video/audio and implement optimized methods for speech-to-text conversion. Moreover, with real-world understanding of integrating premium features through revenue-generating models on platforms such as Apple In-App Purchase and Google Play Billing, I can ensure seamless subscription control on your app. Given my decade-long experience in software development ranging from small business websites to complex portals accelerating development using AI-assisted tools, I'm capable of providing high-quality results at every step of this project.
$90 USD in 5 days
5.3
5.3

As an experienced developer with over 9 years in the industry, I have the expertise you need to turn your CAPTION MASTER app idea into a reality. With proficient skills in Android, Flutter, Google Firebase, iOS Development, and Mobile App Development, I am well-equipped to handle all aspects of your project. My team and I will carefully review your existing code, backend, and Figma design to understand what's missing and come up with a clear plan for implementation. For backend development, we can either continue using the existing Python/Flask setup or rebuild it in a more efficient manner for optimal performance. We'll create stable API endpoints for seamless communication between your app and backend, handle video uploads securely and process them using FFmpeg. For Caption generation, we'll deploy reliable speech-to-text API like Whisper to ensure high accuracy. Additionally, I have significant experience with revenue integration that would be perfect for handling your subscription system. This includes professional experience with RevenueCat integration as well as Native Apple In-App Purchase with Google Play Billing. As requested, we can also handle Firebase Setup for user authentication, saving user projects and tracking premium status if needed. In short, my extensive hands-on experience combined with my deep understanding of backend development and APIs would ensure effective delivery of your video caption app project
$140 USD in 7 days
5.3
5.3

Dear Sir/Madam, I am Kishore Patidar, a professional Mobile App and Python Developer with strong experience in building scalable, production-ready mobile applications and backend systems. I specialize in Flutter (cross-platform), Android (Java/Kotlin), Firebase, Supabase, Node.js, FastAPI, and Django. I have successfully delivered multiple live apps on both Google Play Store and Apple App Store, including fintech, healthcare, education, social networking, and on-demand service platforms. My expertise includes: • Cross-platform mobile app development (Flutter) • Backend API development (Node.js, FastAPI, Django) • Payment Gateway integration (PhonePe, Razorpay, Stripe) • Real-time chat & notification systems • Admin panel & dashboard development • App deployment & store publishing • Secure authentication & role-based systems I focus on clean architecture, scalable backend design, optimized performance, and smooth user experience. From idea to deployment, I can handle complete end-to-end development. I would be happy to discuss your project requirements and deliver a reliable, high-quality solution within timeline. Looking forward to working with you. Best Regards, Kishore Patidar Mobile App / Python Developer
$200 USD in 15 days
4.8
4.8

As a seasoned developer with a detailed understanding of API and backend development, I'm confident that I can help you complete CAPTION MASTER to its full potential. My proficiency extends across both iOS and Android platforms with Flutter, making me a versatile and knowledgeable candidate. Understanding your existing projet, I assure you a thorough review of the Figma design, Flutter app code, and backend code to identify any missing or incomplete elements. Whether it means improving or rebuilding the backend using my experience with Python/Flask or integrating reliable APIs such as Whisper for speech-to-text and translation service, I'll ensure your vision aligns perfectly with the final product. Finally, my deep understanding and prior experience in Firebase setup offers an added advantage in incorporating user logins, anonymous or email-based login options along with seamless saving of user projects - features which can prove invaluable while building CAPTION MASTER as a professional application for serious content creators.
$150 USD in 4 days
4.9
4.9

نقوم ببرمجه مواقع الانترنت وتطبيقات الموبايل نقوم بعمل فيديوهات متحركة وتصميم الشعارات نحن فريق من المطورين ذوي الخبرة في تطوير مواقع الانترنت والتطبيقات المحمولة. لدينا خبرة واسعة في استخدام احدث تقنيات برمجة التطبيقات مثل Flutter و Firebase و RevenueCat، وهذا يجعلنا الخيار المثالي لتكملة تطبيقك CAPTION MASTER. فريقنا لديه القدرة على دراسة الكود الحالي بعناية وتحديد ما يعمل بالفعل وما يحتاج إلى استكمال أو تحسين. واحدة من نقاط قوتنا هي الخبرة في التعامل مع أشرطة الفيديو ، سواء من حيث رفعها ومعالجتها أو انشاء الترجمات. سنستخدم إجراءات FFmpeg الموثوقة لضمان المعالجة والكود بشكل صحیح. أيضًا سنقوم بإضافه استخدام حدید ل API مثل Faster Whisper / Whisper-based transcription لاتسباب ترجمه تلقائیه للاشارات. Pitch: كذالك نحن نستخدم RevenueCat في عملية الدفع وفحص حالة الاشتراك ، التي هي تتطابق مع ماذا تبحث عنه. نحن أيضًا لدينا من الخبرة الوافرة في عملت مع Apple In-App Purchase و Google Play Billing في حال كان هذا هو المفضل بالنسبة لك . ستكونون مسرورين بع
$140 USD in 7 days
4.9
4.9

With over a decade of experience in mobile and web app development, particularly in the realm of AI integration and automation, I am the perfect fit for your Caption Master project. As a former employee of both Google and Apple, my technical prowess and intimate understanding of app store-ready solutions aligns seamlessly with your project's aspirations. I am no stranger to reviewing existing codebases and improving upon them to ensure a streamlined, maintainable architecture. My multi-faceted skillset covers not just API development but also mobile development on both iOS and Android platforms, which is highly relevant for your cross-platform nature. Moreover, I have direct experience with subscription systems like Apple In-App Purchase and Google Play Billing as well as Firebase setup including user login and project saving. My in-depth knowledge of Flutter will prove vital in connecting the backend to your pre-existing frontend app smoothly. Finally, my familiarity with ffmpeg, transcription services, SRT subtitle generation will enable me to complete the backend effectively.
$500 USD in 7 days
4.9
4.9

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