I took some good photos. Perhaps next time I will make some videos. Overall it was a very useful experience, not least just to demonstrate how many things I had to improve. I was quite proud of being able to make many small changes whilst people were playing (I had my laptop so was able to build different APKs and zap them straight over to the phone inside the suitcase using Google drive). I actually went from version 1 to version 5 over the course of the two days.
I am on the train home now. I’m going to build version 6! Later, or possibly tomorrow, I will write more.