In reply to ebdon:
We originally had a book for the routes and it was nice to physically write it out, but once we got a lot of routes it became a bit of a faff to search through them for quality problems / problems of the right grade / tell what the problem was from a glance. I've seen people use A4 books with a page per route, where each page is a picture of the board and you can place stickers on the holds directly - that would solve the problems we encountered logging them in a notebook, but is also a lot more effort to do than just downloading an app! I imagine when we get a nicer training space I'll go through the effort to make a nice book like that, but for now it would be a little out of place compared to the quality of the space lol.
So we use an app called BoulderChallenge, it's paid but only a few pounds. Adding a wall is free and its easy to use although a bit bare bones UI wise. Only downside is others have to pay too if they want the app on their phone while you climb together.
For keeping chalk levels down we just use liquid chalk only and have a fan running towards the window. Seems to keep it low enough to not be noticeable even with a couple of you in a relatively small space for a few hours.