Sounds like an interesting product,
And I wish Gemini success. I do like using a real keyboard... banging away on glass just doesn't give the same effortless satisfaction of a real interface. Palm was OK for what it was, but for real work you need real tools.
One thing Id like to explore is spinning a PDA from a Raspberry Pi, small touch panel display, and a decent Bluetooth keyboard. Attach Pi to the rear of the monitor, filling all remaining surface area with LiPol batteries.
You would get near desktop power that would fit in your pocket...
Also, check this out: gutting and modernising a Psion:
https://hackaday.com/2016/05/01/upgrading-a-20-year-old-pda/
Biting the hand that feeds IT
