Compass App with external USB OTG or BT connectivity

I need to obtain the compass heading for a hardware project. I thought it would be simple to obtain compass heading via the USB OTG port or via Bluetooth,

Is there an Android compass app or any other app that can transfer compass direction via USB OTG using serial protocol, say at 100Hz? Or maybe the same data via Bluetooth serial?

Is there a compass app builder who would like to add this feature to their compass app?

Thanks in advance.