Project state - back PCB finished; time for software! | Details

Back PCB finished! It's the least pretty PCB of all them. I was hurrying to send it off because I need to make the next prototype. The layout was also pretty constrained - Pi Zero, expansion headers, MCP23017 and GSM modem sitting flush from one side, TP4056, USB port, DC-DC and RTC from another. Routing could have been done prettier, but overall it's still good and I reached most of my goals. All the PCB files, including Gerbers, are on GitHub now.

Features planned but scrapped:

General-purpose high-power LED (maybe better left as a mod? Will see when I'll be routing the board next time)
Simple solution for hardware low-power shutdown - I need to consult some people about using TL431, I apparently didn't understand something about making a circuit that'd switch a MOSFET at 3V and have some hysteresis as well.
Bringing out MCP23017 GPIOs taken by the RGB LED on testpoints - just not enough board space. There are two more GPIOs on the MCP that are free, I just forgot to bring them out - that's a task for the next revision (along with refactoring the routing)

Now, onto software goals. I aim to make the first revision of software limited, but polished. I think it makes sense to include the following features:

Phone calls and SMS, rudimentary phonebook
Simple number-keys-to-characters input (like on all mobile phones with a number keypad)
A simple "nmap" app that scans the WiFi network the phone's connected to
WiFi module power management
RGB led control for notifications
Twitter feed reader
Music player
Camera app

That should be enough for two weeks of challenges. Then, I should have enough requirements for the UI framework collected so that I know how the next version should look and can start planning the architecture for that.

Current roadmap adjustments:

3. Start developing v1.0 of software while Chinese festivities go on
    a) Coordinate the contributors, finally send out the alpha boards
    b) Once the festivities end, order a batch of boards and components 
4. Once OSHPark boards arrive, test them, make a new PCB file release
    a) Find who's interested in reviewing kits
5. Once boards&components arrive, make kits and send them out
    a) Prepare the crowdfunding campaign

That's it for project state right now. Next week I can tell you any cool things I'll be able to achieve with the software - hopefully, I'll manage to make at least one of them this week!