Me and my brother Andreas SM6UNC have built us each a hotspot with MMDVM_HS_Hat_hotspot, Raspberry Pi Zero and Pi-Star. MMDVM_HS_Hat_hotspot can handle D-Star, DMR, P25, NXDN, YSF and YSF Xmode at the same time! Is not that incredibly cool!
MMDVM_HS_Hat_hotspot is very reliable and i can truly recommend you to bild your hotspot on MMDVM_HS_Hat_hotspot (Open Source : MMDVM (Multi-Mode Digital Voice Modem) – HAT (Hardware Attached on Top)).
To be QRV on D-star and on and other digital modes are a great way to be a radio amateur!
Kenwood TH-D74E and my hotspot 
MMDVM HS Hat 
