The GD-73A (TYT MD-430) is a low powered dual timeslot UHF DMR/FM radio that's recently been released for the amateur radio use.
I believe that the original purpose of this radio was to fill the Family Radio System or the European 446MHz short range with limited power and a fixed antenna.
However Radioddity are targeting the hotspot roll where you are generally only a few meters away from the hotspot. So it has two power levels, 500mw (low) and 2w (high)
My first impression is that the radio is comfortable in the hand, but has a very light PTT button. So it's pretty easy to key the radio when you don't mean to! The battery life is approximately 2 days just receiving and around 8 hours on transmit on high power (2w)
The small form factor is a comfortable size, but that PTT needs to be fixed. The provided programing software is fairly typical for a Chinese built radio, it's not the best, but it does the job. It lacks any ability to import/export to CSV files like most other radio's support.
So I've entered the relatively new digital modes (for me anyway) of DMR & YSF. This requires either a digital repeater or personal hotspot to access. The popular way to do this is with a software suite called MMDVM and currently there's two Raspberry Pi images available that take care of having to build everything yourself. The first is PiStar and the other is by KB5RAB
I'm using the Pi-star image as it's headless (meaning it doesn't require a keyboard & monitor to run)and uses a webui to configure and uses a read-only file system once everything is loaded, whereas the KB5RAB is a full Raspbian desktop. As you can see from the pictures I'm using a Raspberry Pi2 and the ZUMSpot Pi and a dual colour OLED.
When portable I have 10000 (mAh) 5v power pack that is about the same size as the case I'm using for the Pi2, so a few rubber bands double looped holds it all together rather nicely! The ZUMSpot Pi hat is the perfect size for fitting the OLED screen inside the case using some double sided foam tape stuck to the HDMI socket and the very top edge of OLED is resting on the CPU heat sink. Initially I was going to attach the I2C ribbon cable to the bottom of the Raspberry Pi, but if I ever want to swap the ZUMSpot out I'd be without the OLED so instead I attached it to the ZUMSpot hat.