React Native Developer — BLE Safety App (Core Bluetooth, Background Mode, SMS)

We are a confidential Australian startup building a companion app (iOS and Android) for a proprietary BLE button device. Core function: detect a double-click button press from a paired Bluetooth device and send a native SMS with the user's GPS location to up to 3 nominated contacts. 5 screens only. No backend. No user accounts. Zero data collection. The complexity is entirely in Bluetooth reliability — app must use Apple's Core Bluetooth framework with background mode enabled, detecting button signal when phone is locked. Fixed price only. Full brief provided under NDA after shortlisting. To apply, please include: BLE/Bluetooth app examples, your approach to Core Bluetooth background mode reliability, fixed price quote for Option A (iOS + Android) and Option B (iOS only), and confirm you will sign an NDA. Start your proposal with: "I have read the brief and have built BLE apps previously." See attachment for more information