I design and deliver production-grade real-time communication systems including video conferencing, live streaming, VoIP, and messaging platforms that must perform reliably at scale. With over 15 years of experience in WebRTC and telecom technologies, I have built solutions ranging from one-to-one calling apps to large multiuser collaboration and broadcasting systems across mobile, web, and backend infrastructure. What I can help you build or fix: ✔ Low-latency audio and video platforms using WebRTC, LiveKit, Janus, or custom stacks ✔ Video conferencing and virtual collaboration applications ✔ VoIP and SIP integrations ✔ Live streaming and broadcasting systems ✔ Real-time messaging platforms and backends ✔ Cross-platform mobile apps for iOS and Android ✔ Debugging complex media issues such as quality problems, device failures, sync issues, and scaling challenges Technical expertise: • Protocols: WebRTC, SIP, RTP, SRTP, RTSP, RTMP, XMPP, HLS • Networking: UDP, TCP, IP, NAT traversal, media routing • Platforms: iOS, Android, Web, Node.js, Go, Python backends • Infrastructure: scalable real-time architectures • Performance optimization and reliability engineering • Twilio, Telnyx, DeepGram, ElevenLabs I have helped startups launch communication products from scratch and assisted established teams in stabilizing systems already running in production. If your project involves real-time audio, video, or messaging, there is a high chance I have solved a similar challenge before. Let’s build a system that works flawlessly in production, not just in demos.

Mobile Tech Lead—Android (Kotlin/Java) | XMPP & Webrtc Expert | Python | KMP | iOS Aware | CI/CD pipelines | Scalable App Development | Android Mobile Engineer | 12+ Years of Experience I have more than 12+ years of experience in mobile app development. I have expertise with native (Java/Kotlin for Android) and have huge experience with cross-platform (Kotlin Multiplatform). I am well versed with Android Fragments and XML layouts as well and have worked on several projects using them. Kotlin Multiplatform (KMP) is an open-source technology that allows developers to reuse Kotlin code across various platforms, including Android, iOS, web, desktop, and server-side, while retaining the benefits of native programming. Google officially supports KMP for sharing business logic between Android and iOS apps. Skills and Expertise: [ ] Extensively using Claude.ai daily for app development and problem-solving—dramatically accelerating build speed, reducing errors, and delivering higher-quality results in a fraction of the traditional development time. [ ] Proven experience managing AI-driven app development using Claude.ai as the primary coding engine, delivering polished, production-ready applications. [ ] Proficient in Java and Kotlin programming languages for Android & iOS (Kotlin Multiplatform) app development. [ ] Extensive experience with Android Studio, SDK tools, and third-party libraries. [ ] Strong understanding of mobile app architecture patterns (MVC, MVP, MVVM). [ ] Expertise in integrating RESTful APIs, handling JSON data, and working with web services. [ ] Familiarity with version control systems like Git for code collaboration and CI/CD for pipelines and auto-build generation. [ ] Knowledge of UI/UX design principles to create visually appealing and intuitive interfaces. Tech Stack: Android:- Programming languages: 1- Kotlin / Java 2- Kotlin Multiplatform for cross-platform app development. Architecture: 1- MVVM Android development tools: 1- Android Studio and Android Developer Tools (ADT) 2- Android SDK & SDK Platform Tools Authentication Methods • Use OAuth 2.0/OpenID Connect for third-party login (Google, Facebook, GitHub) • Implement JWT (JSON Web Tokens) for stateless authentication • Add biometric authentication using Android's BiometricPrompt API • Support traditional email/password with server-side secure hashing Secure Token Storage • Use EncryptedSharedPreferences to store tokens securely • Leverage Android Keystore for hardware-backed encryption • Never store tokens in plain text or regular SharedPreferences • Clear sensitive data from memory after use Session Management • Store access tokens (short-lived: 15-60 minutes) and refresh tokens (long-lived) • Implement automatic token refresh before expiration • Use OkHttp interceptors to attach tokens to API requests automatically • Handle token expiration gracefully with retry logic • Clear all tokens on logout • Maintain session state across app restarts Network Security • Enforce HTTPS for all API communication • Implement SSL certificate pinning to prevent MITM attacks • Configure Network Security Config in AndroidManifest • Validate server certificates properly UI Frameworks: 1- Jetpack Compose 2- Android UI components Crash/product analytics: 1- Firebase Crashlytics. 2- Firebase Performance. Payment Integrations: 1- RevenueCat 2- Google In-app purchases/subscriptions 3- Stripe 4- Razorpay 5- Any other payment gateway. Chats & Calls with E2E Encryption: 1- XMPP & WebRTC. 2- Jitsi for Conference. 3- LiveKit for Conferences. Proposed Approach: I suggest following the Agile development methodology, dividing the project into several iterations with regular feedback sessions. This will ensure transparency, effective communication, and timely delivery of milestones. I will provide regular updates on the progress, seeking your input to make necessary adjustments along the way. Deliverables: [ ] Complete development of the Android application, meeting all specified requirements. [ ] Rigorous testing to ensure the app functions flawlessly and delivers an exceptional user experience. [ ] Documentation, including user guides, API references, and any additional instructions as required. [ ] Assistance with deploying the application to the Google Play Store, if needed.

With 16+ years of experience, I help businesses build scalable, secure, and high-performance communication platforms. I specialize in end-to-end VoIP development, WebRTC applications, and AI-powered voice automation. Core Expertise: VoIP Development (Asterisk, FreeSWITCH, Kamailio, OpenSIPS) WebRTC Apps (Audio/Video Calling, Live Streaming) SIP, RTP, IVR, Call Routing & Softswitch (Class 4/5) AI Voice Bots & AI Receptionist Solutions UCaaS, CPaaS & API Integration (Twilio, Plivo, etc.) Media Streaming & Low-Latency Systems Scalable Server Architecture (AWS, Docker, Kubernetes) CRM/ERP & Third-party Integrations WebRTC Application Development - Audio & Video Conferencing - WebRTC, Jitsi, Twillio, OpenTok, Kurento - Screen Sharing, Recording - Online Tutoring and E Learning - Telemedicine and Health Applications - Video Broadcasting and Live Streaming - SFU, STUN & Multiple Server architectures VoIP Service: - Asterisk/Freeswitch/OpenSIP/Kamilio setup & Configurations - PBX System & Software Development - Unified Communication Software - CallCenter Softwares - DID Management - Auto/Predictive Dialer - Mobile or Sip or VoIP Dialers - Real Time billing software - Distributed Server Architecture - Load Balancing and failover setup - Server Administration, Maintenance & 24*7 Support AI-Integration and Automation - Smart voice agents (inbound & outbound calls) - AI chatbots for web, WhatsApp & apps - Speech-to-text & text-to-speech integration - Multilingual conversational systems - Call automation (sales, support, reminders) - AI receptionist and appointment setter - AI content generation (text, image, audio) - Knowledge base chatbots - AI copilots for internal teams - Integrated LLMs for context-aware, deterministic voice interactions Technology, Platforms and languages expertise: Frontend Web: Angular, React.js, Vue.js, PHP Backend: Java, PHP, Laravel, Node.js, Python WebRTC: Native, Kurento, Tokbox, Jitsi, janus, OpenVidu VoIP: Freeswitch, Asterisk, Twillio, Kamilio, OpenSIP, FusionPBX, FreePBX, SIPJs AI/ML: OpenAI, Whisper, ElevenLabs, n8n, Retell

I am working In VoIP , Android and iOS since last 12+ year. I have provided wide range of Technical solutions in VoIP, WebRTC, Website and Mobile Application development areas to startups , mid level and enterprise companies. I have expertise with VoIP mobile development, Android/iOS application development, Flutter Development, ReactNative Development and Web application developments with specialty in developing Asterisk, FreeSWITCH, OpenSIPs, Kamailio, OpenSER, VoIP/SIP, ASTPP, WebRTS and Mobile VoIP based solutions. I have worked on 25+ Linphone, PJSip and WebRTC Based Mobile VoIP Diallers with 100% Client satisfaction. I can also provide customized Class-4 and Class-5 Softswitch for your VoIP business. Please refer below services I can provide. - Linphone Mobile VoIP Dialler development - PJSIP Mobile VoIP Dialler development - Asterisk Server Installation, development , customization and maintenance. - FreeSwitch Server Installation, development , customization and maintenance. - Kamailio and OpenSips Server Installation, development , customization and maintenance. - Android Application development - iOS Application development - Web Application Development - RectJS and ReactNative Web and Mobile Application development. - Testing and bug fixing in existing applications. - Consulting for ongoing projects. - Can provide consulting for projects related to Android, iOS, ReactJS, Asterisk , FreeSwitch , Opensips, Kamailio, ASTPP, RTPengine, MediaProxy, RTPproxy, FreePBX and A2Billing. - Expert in developing Flutter WebRTC Applications. - Expert in developing ReactNative WebRTC Applications. ✅ Mobile Softphone development - Linphone, PJSIP, WebRTC, Any Proprietor SIP SDK integration, Agora Integration, LiveKit Integration, Custom WebRTC Development ✅ VoIP - Freeswitch, Asterisk, FreePBX, FusionPBX, Kamailio, Opensips, ASTPP ✅ React - ReactJS, NextJS, ReactNative, Mobex, Axios, MaterialUI, React-Bootstrap, TailWindCss ✅ NodeJS - NodeJS, NestJS, Middleware, Typescript, Javascript, AWS Deployment, CI/CD Deployment ✅ Mobile Application - Flutter, ReactNative, Android Kotlin, Android, Swift, Objective-C, SwiftUI ✅ HTML, JS, CSS, Bootstrap, Vanila Script, Jquery ✅ WebRTC Server Customization : Livekit, Mediasoup, Janus, Agora, libwebrtc You can message to discuss your requirements in detail.

I’m a seasoned Full Stack Developer with a wealth of experience, having dedicated 8 years to the roles of Software Developer/Architect. My specialization lies in the realm of Mobile App development with a particular focus on creating innovative solutions for a wide spectrum of industries, with particular emphasis on chat-related and AI-related applications Initially, I had started my journey with “Accenture” and after having a good enough experience and knowledge I’ve started to work on my own as an independent freelancer" I’m completely available with an excellent solution and provide the best industry experience. --> Our experience & Area of expertise: I’m very passionate about creating intelligent systems that push the boundaries of human-computer interaction. With 3 years of experience in the field, I have honed my skills in developing cutting-edge AI solutions and bringing transformative ideas to life. Related to Database; I've worked with SQL relational databases like MS-SQL, MySQL, PostgreSQL, Oracle DB and no SQL databases like MongoDB, DynamoDB and Elastic search. I have strong hands on experience working with Firebase and have worked with following Firebase services as: -- Live Database -- Fire Store -- Firebase Functions -- Analytics -- Ad mob integration -- Notifications -- Test labs Worked well with the following Cloud AWS Services like below: -- Lamba -- Ec2 -- S3 -- Fargate -- Cognito -- Route 53 -- SNS -- Api Gateway -- EBS -- RDS -- Elastic search and Kendra. And good working knowledge with other Cloud Services : -- Azure -- GCP -- Linode -- DigitalOcean and Docker based images. Backend Development: I’m very good with ( Java as well as Node.js ). I’ve worked with following Java frameworks as below; -- Spring boot -- Spring MVC -- Spring security -- JPA, Hibernate -- JSF I have developed more than 100 applications in Mobile (Android/IOS), Desktop (Windows/Linux/Mac) and web applications for the different industries and their links such as; -- Instant Messaging/ Voice/ Video calling (WhatsApp/Telegram/Wechat) -- Food Delivery (UberEats/Swiggy) -- Cab booking apps (Ola/Uber) -- Hospital management (Doctor/ Patient appointment schedule) -- Booking system (Movie ticket booking / Postpaid/ Prepaid Recharges) -- Wallet management (Fund Transfer / Pay using wallets) -- Fantasy games (Dream11/ Sorare) -- Crypto based NFT minting platforms -- Dating apps (Tinder/ Bumble) -- Social media apps (Tiktok/ Facebook) -- Media streaming apps (Netflix) -- Fitness Apps Please take a look and ensure yourself that we are very good at delivering your requirements in a very professional way. Let’s discuss ahead.

i can handle full development cycle that is proved by my numerous completed projects where i worked alone or in a small groups.

🏆 Top-Rated Upwork Freelancer ⭐ 5-Star Ratings from Valued Clients 🚀 50+ Successful App Deliveries on Flutter 🎯 100% Job Success on Upwork Transform Your Vision into a High-Performing App Whether you need an MVP, a full-scale Flutter or app, or a tailor-made integration, I am dedicated to surpassing your expectations. 👋 Hi, I’m Jaydip! With over 9 years of mobile app development experience, I specialize in Flutter, and Kotlin, crafting high-quality solutions for industries like social networking, business, education, entertainment, health, and travel. 🤝 Why Clients Choose Me for Long-Term Partnerships: 🔰 Proven Technical Expertise – 9+ years of hands-on experience 🔰 Accurate Estimates – Transparent and realistic project timelines 🔰 Consistent Communication – Daily progress updates 🔰 Client-First Approach – Your satisfaction is my top priority 🔥 My Core Skills & Specialties: ✔ Cross-Platform: Flutter ✔ iOS Development: Swift, Objective-C, Xcode ✔ Android Development: Java, Kotlin ✔ Backend Tech: Laravel, NodeJS ✔ Cloud & Database: Firebase, Realm ✔ Web Services: XML/JSON, REST/SOAP ✔ Real-Time Chat: XMPP, Openfire ✔ Payment Gateway Integration ✔ GPS-Based Tracking & Navigation 📞 Let's Collaborate! Ready to turn your app idea into a game-changing digital product? Let’s connect and make it happen!

Senior Full Stack & Mobile App Developer | 15+ Years of Experience I specialize in building scalable Web, Mobile, and Real-Time Communication applications from scratch as well as enhancing existing products with modern technologies and best practices. Core Expertise Frontend: React.js, Next.js, Vue.js, Angular, TypeScript, JavaScript Backend: Node.js, Laravel, PHP Mobile: React Native, Swift, SwiftUI, Kotlin Databases: MySQL, MongoDB, Redis, Firestore WebRTC & Real-Time Solutions Experienced in developing secure video conferencing and messaging platforms using MediaSoup, Jitsi, Twilio, XMPP, Ejabberd, and Erlang. API & Payment Integrations Firebase, Google APIs, Facebook API, Adobe API, Stripe, PayPal, Braintree, Flight Tracking API, Foodics API, and more. I focus on delivering clean architecture, scalable solutions, and high-quality code with clear communication and a commitment to long-term client success. Available for Web Development, Mobile Apps, SaaS Platforms, API Integrations, and WebRTC-based Solutions. Let's build something exceptional together.

22+ years in the telecommunications and Software industry from design, development, management, delivery, and lead. Vast experienced focused on solution customization for Cloud Telecommunication System. Specialist in Communication System like Core GSM, IP, SIP, WebRTC, SS7, Radius, Diameter, SMPP, XMPP, SNMP, Sockte, RabbitMQ Message Broker, Software Defined Radios (SDR), and IoT. Also capable to develop and deliver any communication-related solution.

With 14+ years of experience, I specialize in iOS & Android app development, delivering high-performance, scalable applications across AI, VoIP, secure communication, streaming, IoT, fintech, fitness, dating, taxi, and e-commerce. My apps are live globally, ensuring seamless functionality and user satisfaction. I actively contribute to open-source projects, driving tech innovation. Key Skills & Expertise Mobile App Development * iOS: Swift, SwiftUI, Objective-C * Android: Java, Kotlin Secure Communication & VoIP * XMPP, Ejabberd, MongooseIM, WebRTC, VoIP, conference programming * VoIP Integration: QuickBlox, Jitsi, Sinch, Agora, LiveSwitch, Twilio, CallKit Emerging Technologies * AI-powered Apps & Chatbots * Blockchain & Wallet Development * Augmented Reality (AR) Industry-Specific Solutions * Health & Fitness: Wellness tracking, workout plans, fitness goals * Medical Apps: Telemedicine, patient monitoring, appointment scheduling * Call & Conference Apps: VoIP calling, video conferencing, secure communication * Dating Apps: Advanced matchmaking, secure chat, user privacy * Taxi & Ride-Hailing Apps: GPS navigation, payment integration * Restaurant & Logistics: Food delivery and fleet management Streaming & IoT Connectivity * Streaming Apps: Audio/video streaming solutions * IoT Connectivity: Bluetooth/BLE integration with IoT devices Additional Expertise * Custom Jitsi Solutions: UI/feature customization * Device-Specific Development: iPad, Mac OS, Apple Watch * Payment & API Integration: Stripe, Firebase, Google Libraries * Real-Time GPS Tracking: Google/Apple Maps integration * Optimization & Maintenance: Bug fixing, code refactoring, performance tuning * App Deployment: Apple App Store, Google Play, TestFlight Work Approach & Values * Clear Communication: Regular updates and transparency in every step * Efficiency & Time Management: Delivering projects on time, without compromising quality * Independent & Team Player: Comfortable working solo or in collaborative environments * User-Centric Development: Focused on high-quality apps that drive engagement & success Why Work With Me? I am passionate about crafting scalable, feature-rich, and impactful applications that combine cutting-edge technology with a seamless user experience. My ability to deliver high-quality solutions quickly and efficiently has earned me long-term client relationships and top-tier satisfaction ratings. Let’s collaborate to bring your vision to life with a world-class mobile application! 🚀