Full Stack Engineer

About ONLYQ

ONLYQ is building the world’s most advanced  ultra-slim, clinical-grade health wearable —combining premium materials (ceramic, sapphire, FKM), multi-sensor physiology (PPG, ECG, EDA, Temp, IMU), and real-time AI analytics.

Backed by  Cymetree Projects LLP , a high-growth multi-vertical enterprise (USD 340M projected revenue this year), ONLYQ is a  self-funded, long-term premium hardware–AI ecosystem  with global ambitions.

We’re assembling a world-class team to launch our Gen-1 wristband and mobile app—designed to compete with WHOOP, Oura, Garmin, and Apple.

Role Overview

We are looking for an exceptional  Senior Full-Stack Mobile Developer  with deep experience in  Bluetooth Low Energy (BLE), real-time sensor streaming, and native mobile development (iOS + Android) .

This is a  core team, high-ownership role  responsible for building the ONLYQ mobile app from scratch—architecture, BLE integration, data pipelines, backend APIs, and production-quality UI.

You will work closely with our firmware, sensor, and AI teams to deliver a world-class health and wellness experience.

What You Will Build

• Native iOS and Android apps for ONLYQ (Swift + Kotlin)
• High-stability BLE pipeline for PPG / ECG / EDA / Temp / IMU streaming
• Real-time data ingestion, processing, caching & cloud sync
• Backend API layer (Node.js or Python)
• AI / ML model integration (sleep, HRV, stress, readiness)
• Beautiful dashboards and wellness visualizations
• Secure user authentication, subscription, and cloud services
• CI / CD pipelines & scalable architecture for future V2 / V3 hardware

Key Responsibilities

Mobile Development

Build  native iOS  apps using Swift, SwiftUI, Combine

Build  native Android  apps using Kotlin, Jetpack Compose

Implement CoreBluetooth & Android BLE stack

Optimize MTU, GATT, reconnection logic, and background sync

Ensure ultra-reliable sensor data capture (5–50 Hz)

Backend & API

Build REST + WebSocket APIs (Node.js or Python)

Implement data storage (PostgreSQL / MongoDB)

Setup cloud infrastructure (AWS / GCP)

Ensure secure data flow & low-latency analytics

Data & AI Integration

Integrate physiological AI models (Python / TensorFlow Lite)

Work with our biosensor engineering team

Implement signal cleaning, annotation & time-series sync

Architecture & Quality

Implement MVVM / clean architecture

Automated testing, CI / CD pipelines

Optimize for battery life, background execution & stability

Deliver smooth, polished UI interactions with animation support

Required Skills

Mobile (Mandatory)

Expert in  Swift / SwiftUI / Combine

Expert in  Kotlin / Jetpack Compose

Strong experience with  BLE GATT communication

Experience with real-time sensor data processing

Experience with background services & multi-threading

Backend

Proficient in  Node.js  or  Python (FastAPI)

Database experience : PostgreSQL or MongoDB

Experience with AWS / GCP / Firebase

Wearable / Health Data

Understanding of HR, HRV, ECG, IMU, Temp, or other biosignals

Experience working with wellness, fitness, or IoT devices

Bonus Skills

Experience with TensorFlow Lite / CoreML

Experience with time-series data & signal processing

Experience building subscription-based apps

Knowledge of Apple HealthKit / Google Fit

Who Should Apply

You are a  top-tier developer  with a strong engineering mindset

You’ve worked on  smartwatch / IoT / fitness apps

You want to build a  global premium product from Day 1

You enjoy solving deep Bluetooth, data, and architecture problems

You want ownership—not just a coding job

What We Offer