If you are having trouble connecting your app to a sensor there are few quick fixes we recommend that will remedy 99.9% of issues!
1. Reseat the battery by removing the battery lid (and battery). Sit the battery back down such that the branding on the battery faces outward. Press the battery lid back down. The sensor should blink red. If it does not, try a new battery.
2. Ensure Bluetooth is enabled on your device. This permission can be found in the settings app on both iOS and Android phones.
3. Your device could be stuck in "DFU mode." This is a factory setting from the manufacture so in a warehouse of hundreds of thousands of sensors, they can easily find a specific sensor. To fix this open your settings menu in the Beyond Pulse App. Select Belt Recovery. You may see "DFU Targ" listed. Select 'DFU Targ' and your sensor will do a reset.
4. Disconnect other bluetooth devices. Are you connected to headphones? your car? a speaker? Disconnect from those devices then try to perform your action in the Beyond Pulse app (this is a common issue on Samsung Devices as Samsung does not share the same bluetooth settings as other androids).