On top of those above, I also have KG Free which is a good guide for tying a small number of knots

Depends what you mean by 'survival' but I find the app 'ShowTheLoo' great when out and about!

I think that in a real emergency, the mobile network will most likely grind to a halt, so I am not planning on relying on anything that needs it. However, I have downloaded a free PDF reader and am in the process of digitising all my important documents, so if I have to evacuate I have a readable electronic copy of it all with me (as well as paper versions). Also for public transport routes and timetables etc, anything that could help me get home. And downloaded maps for the area.