In doing more evaluation on Qubie Zero, we ran across some issues with the documentation that would have potentially prevented a successful build; so we've fixed those in the repository, and the instructions in INSTALL.md should now work on basically any Raspberry Pi hardware (keeping in mind not to build the Bluetooth stuff on hardware without Bluetooth).

We've also done some head-to-head power benchmarks using the same 13400mAh battery pack, and found that Qubie runs for about 24 hours, while Qubie Zero runs for about 40. That is, Qubie Zero runs 66% longer on the same battery — which is great for deployment in polling places, as it means we can use much smaller and cheaper batteries (on the order of 5000mAh, at a cost of about $5) to get Qubie Zero through an entire day at a polling place.

Of course, these power numbers will change dramatically in future versions of Qubie when we are uploading information in real time for analysis and reporting... but it's a much better starting point.