Need a Bluetooth FOB key to pair with and activate a mobile app

[AC Question]

Looking for a programmable Bluetooth FOB key solution for a Mobile app.
We have developed a security app for women. Using a Bluetooth FOB key, the user can press the FOB key to activate and automatically start the security app (which records Video and Audio) in case the user senses any danger. They do not need to start the app from the smart device.
Any help is appreciated.