There are two hardware options – a RPI and USB unit.
ZUMSPOT RPI (https://www.moonraker.eu/mmdvm-nano-hotspot-5495)
This is a RPI unit which supports multiple modes and contains a 1.3″ OLED display. It can be connected to a computer or raspberry pi and uses the BlueDV software.
ZUMSPOT USB (https://www.moonraker.eu/mmdvm-nano-hotspot-5496)
This USB dongle supportds multiple modes. It can connect to any device that can utilise BlueDV including mobile phones via an OTG cable (check the Hotspot/Software menu). Whilst BlueDV is available for various platforms (Android, iOS, Windows and Linux), each version differs, with the WIndows version being more up todate. The Zumspot USB will also work with Pi-Star on a Raspberry Pi. I suggest using v4 of the Pi-Star software and select modem type “Zumspot USB Stick”.