I decided to shuffle the functions slightly. There are a lot of basic / measurement functions on the SS, that are useful, though not all the time. Some of the functions will need additional hardware not yet purchased (e.g. C12666MA Spectrometer, or a GPS module), but I've included them for completeness sake. Here's the current break down of functions I've added:

Functions to be added soon:

1. Pen. Still not sure what the best approach is in this case. ML models aren't supported a ATSAMD21. Other ideas like Hopfield Networks could work be implemented, though they are significantly limited in terms of memory. I could also offload the identification / classification to a server, and just have the SS record the pen strokes, but this is less fun.

2. Analog Broadcast. I saw a video where an ESP8266 was used to broadcast analog tv. Might try something like that.  

3. Smart Home. Connecting the SS to other appliances at home, possibly using wifi router signals as positioning beacons. 

Other things to do:

1. Enclosure. Redesign case to look less pedestrian, and more sci-fi.

I like where the project is at the moment, though there's a lot more I'd like to add and change. For now though, I'm putting it on a bit of a hold. I'll work on things more slowly and apart, but will pick it up again in a few weeks.