Development of API for Android Hardware

We are working on a mobile phone that requires the function of an SOS emergency alert app. Looking for a developer that can program the Google Assist button to activate the SOS app. Project Activity and SOW: 1. Investigation and Feasibility 2. Documentation 3. Estimate of cost 4. Timeline 5. Execution Solution outline - 1. We are using an off the shelf Nokia android handset from HMD Global. 2. App will be deployed in a MDM environment in kiosk mode 3. The SOS emergency alert app is scoped to the external Google Assist Button on phone. In other words the Google Assist hardware button needs to be remapped to trigger the SOS map instead of Google Assistant. 4. Phase 1 of Project is to develop API or other workaround to be able to remap Google Assistant Button. This would then be able to work with SOS App. 5. SOS app to have countdown timer of 10 secs, cancel, sms alert to emergency contact list of 5, sms alert to include last known location and announce emergency to contacts, dial emergency number, speaker on for 2 way voice with emergency services 5. Purpose of API is to be able to easily make changes if and when hardware or software updates occur via the MDM with updated APK. This API would also easily allow integration to other accessories to phone such as a wearable Bluetooth hardware pendant without expense of developing new apps. 6. Phase 2 is future use of API and would be part of another project. It would be to further enhance API for IOT environment and accessories. Requirements yet to be finalised. 7. You will be adept at development with Android SDK and android hardware 8. Please post examples of similar projects with your proposal 9. Option to just develop API for hardware or API for hardware with SOS app.