Open to opportunities

Umair User

@umairuser7

Senior Android developer with 7+ years building high-performance mobile apps and SDKs using Kotlin, Jetpack Compose, and KMP.

Zimbabwe

Message

What I'm looking for

I’m looking for a role where I can build secure, high-performance Android/Kotlin Multiplatform apps and SDKs, improve UI/UX and reliability, and partner cross-functionally to deliver scalable BLE, payments security, and clean architectural solutions.

I’m a Senior Android Developer with 7+ years of experience building high-performance mobile apps and SDKs. I focus on modern Android architecture and security-first engineering, from UI/UX to reliable performance.

At Devsinc, I led end-to-end development of healthcare and e-commerce apps, including optimized user transactions and backward-compatible experiences across mobile and tablet. I also built a secure KMP-based SDK using AES/RSA/Argon2 encryption, sealed-box messaging, hardware-backed keystore, and root/emulator detection.

I’m hands-on with complex integrations—BLE scanning, bonding, GATT operations, MTU negotiation, and background-safe reconnection flows—while delivering secure payment journeys with SSL pinning, reCAPTCHA Enterprise, and 3D Secure. I improved stability using New Relic and Firebase Crashlytics, reducing crash rates by 30%.

I care deeply about Clean Architecture, MVVM, and scalable patterns, and I mentor junior developers to keep best practices consistent. I’ve also worked on LLM-focused dataset creation and evaluation, strengthening model accuracy through careful prompt engineering and quality validation.

Experience

Work history, roles, and key accomplishments

Current

Senior Android Developer

Current

Devsinc

Jan 2025 - Present (1 year 6 months)

Led end-to-end development of healthcare and e-commerce Android apps, improving transaction flows and app performance. Built a secure Kotlin Multiplatform SDK and implemented BLE and secure payment flows, improving crash rates by 30%.

Kotlin Kotlin Multiplatform RSA Argon2 Bonding GATT MTU Negotiation Android Reconnection Flows SSL Pinning ReCAPTCHA Enterprise 3D Secure New Relic Firebase Crashlytics MVVM Clean Architecture Jetpack Compose CI CD GitHub Actions Firebase App Distribution

LLM Android Engineer

Turing

Nov 2025 - Jun 2026 (7 months)

Designed and evaluated datasets and model outputs to improve LLM accuracy, relevance, and alignment with task requirements. Performed prompt engineering and comparative response analysis while defining data annotation guidelines and quality standards.

LLM Evaluation Output Review Correctness Coherence Alignment Scoring Prompt Engineering Comparative Analysis Data Annotation Data Validation Summarization Q&A

Software Engineer

Devsinc

Feb 2022 - Dec 2024 (2 years 10 months)

Developed Android apps with a focus on UI/UX, BLE communication, and API integrations. Implemented BLE read/write and notifications, migrated Java to Kotlin, and integrated Retrofit/Moshi/OkHttp for online/offline API communication.

Android UI BLE Writes Notifications Custom GATT Profiles Cross Device Compatibility Kotlin Java Migration Retrofit Moshi OkHttp Junit Mockito Espresso BLE Permissions Background Limits

Software Engineer

BrainX

Feb 2020 - Jan 2022 (1 year 11 months)

Built and maintained scalable Android applications focused on performance and usability. Worked with multi-threading and RxJava for responsive experiences and supported CI/CD automation improvements.

Android Development Performance Optimization RxJava Asynchronous Programming