We are currently busy completely re-engineering the entire Bluetooth Low Energy module. This will also include that Bluetooth is started on demand and will also be disabled when you close the app.
To avoid BT being turned on with the current release, you can simply select a non-BT type of heart rate sensor in Configuration >> Sensors (e.g. "ANT+ HRM").
When I start RunGPS (3.0.4) Bluetooth is enabled automatically. If I am not using any Bluetooth devices this drains my battery before I can complete my training! RunGPS needs a Configuration setting to control Bluetooth! Also after I quit the application Bluetooth is still left running.
I have noticed that in 3.04, run.gps turns on my phone's Bluetooth when the app is launched without asking permission. I don't think it used to do this? It always asks to turn the GPS on. And I thought this was against Android protocol?