Jorge S.

Flutter, FlutterFlow, and Android mobile app developer, with 10 years of experience building apps used by millions of people at GrubHub and MyFitnessPal. I take over existing apps and keep them shipping, build new ones from scratch, and add AI features that actually work in production. 12 Upwork projects, 100% Job Success, based in Rhode Island for real US time-zone overlap. My work covers health and fitness (MyFitnessPal, EmergencyID), restaurant ordering (GrubHub's SDK behind 200+ brands like Subway and Wendy's), social (Pzzlrs), and education (Mind Garden). Most freelancers can either build a whole app on their own or have big-company experience. I have both, and that's what makes the difference between an app that launches and an app that holds up after launch. The build-it-myself side: I've taken three apps from a blank page to the App Store and Google Play as the only developer, handling the design, architecture, backend, testing, and store submission for each one. Pzzlrs: a social network for puzzle players with a real-time feed, push notifications, groups with admin and moderator roles, custom-built search, and leaderboards, live on iOS, Android, and the web. I redesigned how its feed data was stored and cut load times by 2-3x. Mind Garden: a gamified learning app with an AI tutor, daily content, streaks, achievements, and push notifications. EmergencyID: an offline-first medical app for first responders with encrypted data, PDF records, and multi-language support, built and shipped in 30 days. The enterprise side is why those apps hold up. At MyFitnessPal I was the sole Android engineer on the Progress Hub, a feature used by 4M+ people every month, and I shipped the Android side of an LLM-powered insights feature a full sprint ahead of schedule. At GrubHub I built SDK features that ran inside 200+ restaurant apps at once, where one bug meant 200 broken apps, so I learned to build carefully. I also led the accessibility compliance initiative across Android and iOS, launched the phone-verification security feature, and modernized a legacy Java codebase to Kotlin. At AndPlus, an agency, I delivered client Android apps from requirements to launch with a 100% on-time record, including work for Onset, a data logger manufacturer whose customers include NASA. Taking over an existing app is something I've done at every job I've had. I start by making sure you own your code and accounts, review the build and release setup, crash reports, dependencies, and security, then give you a clear list of what's solid, what's risky, and what to fix first. Here's what you get working with me. One person who owns the whole thing. You don't need to coordinate a designer, a backend developer, and a mobile developer. I handle all of it, and I'm accountable for the result. Speed without cutting corners. I use AI coding tools every day, but this isn't vibe coding, where someone who can't read the code lets AI generate an app and hopes it works. AI is a force multiplier for 10 years of engineering experience, not a replacement for it. I design the architecture, I review every line before it ships, and I know when the AI is wrong. At MyFitnessPal I was the engineer other developers came to for AI coding workflows. What that means for you is senior-level code, delivered faster. No surprises. You get a working demo on a real device at every milestone, problems get flagged before they turn into delays, and you own your code, accounts, and infrastructure from day one. Clear communication. I explain technical decisions in plain terms, so you always understand what's being built and why. I can help if you're: Taking over an app someone else built and need it debugged, stabilized, and shipping again Starting a new app and need it built and launched on iOS and Android Adding AI features, like an AI chat assistant or personalized insights, to a mobile app Stuck on a project that's slow, buggy, or blocked from the app stores Adding features to an existing Android or Flutter app My stack: Kotlin, Java, Jetpack Compose, Coroutines, MVVM, Flutter, Dart, FlutterFlow, Firebase (Auth, Firestore, Cloud Functions, Storage, Cloud Messaging), LLM integration, REST APIs, Stripe, and Git. I'm available now and taking on new projects. Send me a message and tell me what you're building.