This Android App is a necessary research tool in the field of RFID. It includes proxmark3 universal client. The client comes from the latest RRG Iceman repo.
You can use it to connect your Proxmark 3 RDV4.0 via Bluetooth or USB-OTG. Later, it will be compatible with more devices in the future.

Firmware version: RRG/Iceman// 2019/08/12