Best 2006 TD5 OBD2 Bluetooth diagnostics adapter

Hey there, I'm new to the Defender scene, I just bought my first Defender and I've been fixing a couple of things.

I'd like to use the OBD2 port to get some statistics and some diagnostics.

Does anyone know if there are any good adapters and apps that are good for a TD5? Or is simply buying a diagnostics kit the best way to go :/

Thanks!