Ok I have an ipad pro. I bought Procreate. I've been watching YouTube tutorials on how to use it! It's a great little app, wish I had thought about using it before now.
Referring to my list of 'musts' at all times, I have started to sketch ideas.
Thee List of 'Musts'
Tent
Sleeping bag
Camp chair
Roll mat/Mattress
Clothing, change of shoes and toiletries
Speaker
Alcohol (lets say 20 - 24 cans of beer/cider or 1ltr spirit and 2ltr mixer)
Water bottle - because this is encouraged
Mobile phone etc
More to upload*
Here's a video of me drawing the back of my vest while learning to use the app. It's pretty difficult to control the pen, I have a glossy screen protector, it is suggested that you get a matt one to provide more friction.