Tanjim Ahmed.

Flutter & Mobile App Developer

Tanjim
Ahmed.

I build cross-platform apps that feel native — from the first pixel to the payment gateway.

See my workGet in touch
Based in
Sylhet, Bangladesh
Experience
5+ years
Focus
Flutter · .NET · Azure
Portrait of Tanjim Ahmed

About

Apps built to be maintained, not rewritten.

A passionate Flutter/Dart app developer dedicated to transforming ideas into high-performing mobile experiences. With expertise in cross-platform development and native Android technologies like Kotlin and Java, I create visually appealing and efficient applications. Committed to innovation, open communication, and excellence, I strive to bring your vision to life with cutting-edge solutions.

Today I work across the stack: Flutter and native Android on the front end, .NET and C# services behind them, and Azure DevOps pipelines to ship it all. Recent work spans a multi-platform CRM with Stripe payments and subscriptions, location-based features built on the Google Maps API, and end-to-end test coverage with Playwright.

Mobile

  • Flutter / Dart
  • Native Android (Kotlin, Java)

Web & Backend

  • .NET / C#
  • Vue.js / Next.js
  • REST APIs & middleware
  • SQL / databases

Cloud & DevOps

  • Microsoft Azure / AWS
  • Azure DevOps & CI/CD
  • Firebase

Quality & Tooling

  • Playwright (E2E testing)
  • Git / GitHub

Selected work

Shipped products, not concepts.

Cross-platform apps in production — with real payment flows, offline behaviour and cloud backends behind them.

Mascopia app screenMascopia app screenMascopia app screen

MascopiaIn development

A two-sided marketplace that connects pet owners with trusted walkers, boarders and groomers — booking, live chat and location search in one app.

  • Built the full cross-platform app in Flutter on a Clean Architecture foundation (BLoC, GetIt, Dio).
  • Real-time 1:1 chat with photo sharing over SignalR, plus push notifications via Firebase.
  • Location-based service search on the Google Maps API, with an address and date picker.
  • Owner / Host dual-mode profiles with ID verification and document uploads.
  • Flutter
  • BLoC
  • Google Maps
  • SignalR
  • Firebase
  • .NET
SafeMom — Ingredient Checker app screenshot

SafeMom — Ingredient Checker

A consumer health app that scans product ingredients, with subscriptions and ad-driven growth.

  • Built a consumer health app in Flutter that checks product ingredients and flags what to avoid.
  • Implemented an Adapty paywall to manage premium features and subscriptions.
  • Integrated multiple ad SDKs, including Facebook and TikTok, to drive growth and revenue.
  • Flutter
  • Adapty
  • Ad SDKs
  • In-App Purchases
Range Buddy app screenshot

Range Buddy

A cross-platform shooting-range companion with multi-party payments and real-time sync.

  • Engineered the complete cross-platform application in Flutter, delivering one seamless experience on iOS and Android.
  • Built a scalable Firebase backend handling authentication and real-time data synchronization.
  • Integrated Stripe Connect for multi-party transactions and RevenueCat for in-app subscriptions.
  • Architected with Clean Architecture for a maintainable, testable codebase.
  • Flutter
  • Firebase
  • Stripe Connect
  • RevenueCat
Nightingale app screenshot

Nightingale

An in-car audio experience that keeps working when the signal does not.

  • Extended the app into vehicles with Apple CarPlay and Android Auto for safe, hands-free use.
  • Implemented robust offline caching so key features keep working without a connection.
  • Leveraged Microsoft Azure for scalable cloud services and real-time data synchronization.
  • Built on Clean Architecture as a foundation for future growth.
  • Flutter
  • Apple CarPlay
  • Android Auto
  • Azure
Dent Shop Manager app screenshot

Dent Shop Manager

A CRM for hail and PDR auto-body shops, with subscriptions and in-app payments.

  • Implemented a monetization strategy with RevenueCat to manage recurring subscription plans.
  • Integrated Stripe for secure, direct in-app payments for services.
  • Applied Clean Architecture to keep the codebase stable as features expand.
  • Flutter
  • RevenueCat
  • Stripe
  • Clean Architecture
SERU Training Course app screenshot

SERU Training Course

An e-learning app that helps London private-hire drivers prepare for the TfL SERU assessment.

  • Built the cross-platform app in React Native, shipped to the App Store and Google Play.
  • Lessons mapped to the SERU syllabus, with 200+ practice questions and timed mock tests.
  • Progress tracking so learners can see which sections still need work.
  • Course plans from 2 to 12 weeks sold as in-app purchases.
  • React Native
  • E-learning
  • In-App Purchases
Sol Store app screenshot

Sol Store

A full-featured mobile storefront, from browsing to secure checkout.

  • Developed a complete e-commerce mobile app in Flutter covering product browsing through checkout.
  • Implemented a secure payment gateway for reliable online transactions.
  • Flutter
  • E-commerce
  • Payments
Schedule Pro app screenshot

Schedule Pro

Scheduling that adapts cleanly from phone to tablet.

  • Engineered a fully responsive interface tuned for everything from phones to tablets.
  • Developed on Clean Architecture principles, producing a modular, easy-to-maintain system.
  • Flutter
  • Responsive UI
  • Clean Architecture

Experience

Where I have been building.

  1. Jun 2026 — Present

    Software Developer

    Cerebrum City

    Own end-to-end testing with Playwright, building automated coverage for critical user flows. Support teammates on backend work in .NET and middleware, and go deep on DevOps with Microsoft Azure across CI/CD pipelines and deployments.

  2. Jan 2026 — Jun 2026

    Lead Flutter Developer

    Mascopia Inc.

    Main lead Flutter developer, owning app architecture and release delivery. Built location-based features with the Google Maps API including live tracking and geocoding, and adopted DevOps practices with CI/CD pipelines and automated builds.

  3. 2024 — 2026

    Full-Stack Developer

    Dent Shop Manager

    Built a multi-platform CRM covering shop and customer management. Developed the .NET backend end to end — data models, REST APIs and authentication — and integrated Stripe for payments, subscriptions and automated invoicing.

  4. 2023 — 2024

    Flutter Developer

    Practical Defense Training, LLC

    Reduced development and maintenance costs, improved code maintainability and enhanced the app's scalability, while keeping the experience seamless and consistent across Android and iOS.

  5. 2022 — 2023

    Flutter Developer

    Shiftboard

    Rewrote an entire app from native to a cross-platform Flutter solution, ensuring a consistent user experience across Android and iOS and optimizing backend communication and API handling.

  6. 2021 — Present

    Application Developer

    Upwork

    Designed, developed, tested and deployed mobile applications using Java, Kotlin, Swift and Flutter. Provided direction across phases of the development lifecycle and managed multi-platform regional and national campaigns.

  7. 2018 — Present

    Founder

    Crazybot Studio

    Founded and run my own app development studio.

Education.

  1. 2024 — Present

    BSc in Computer Science & Engineering

    Leading University

    Expected graduation fall 2027

What clients say.

I have hired Tanjim many times, and I would still do it again whenever any need arises. He is very professional and committed. He is attentive to detail, punctual, and is always on time. He makes sure to get business requirements right. It has been a pleasure working with Tanjim.
Mosab Abumarzouk
Tanjim did a great job, completing all work above expectations and in a timely manner, with the work being completed ahead of deadlines. I have very limited understanding of coding, and have ideas that will grow outside of the original scope of work. Tanjim made reasonable accommodations and discussed any budget concerns ahead of time so that there were not any unexpected costs. I look forward to working with Tanjim again in the future.
Jeremy Gill
Hired for a specific purpose to update my mobile app. He did the job well, quickly, and was great with communication. Would hire again.
Ben Silverstein

Contact

Have an app idea? Let's talk.

Tell me what you are building and where it is stuck. I reply to every serious enquiry within a day.

Send a message+880 1518 758860
Location
Sylhet, Bangladesh