So I have decided to choose the Pro Mini because with some mods it has some crazy low battery usage. But I need to use Bluetooth so I decided to ask you, the community, to help me and get an Arduino with low power consumption and Bluetooth. I just need a Bluetooth board which is small fits with the Pro Mini and uses very low power. Maybe you could help me? Thanks in advance for your help.
Arduino_Fan_245325:
I just need a Bluetooth board which is small fits with the Pro Mini and uses very low power.
That is loose language. The popular HC-0x bluetooth boards and BLE are about the same size as a Pro Mini, but it is down to you to fit them together. Since you have low power in mind, you are likely to use the bare modules anyway, which may involve a custom PCB.