Nexus 7 Apps

With my Nexus 7 hopefully being dispatched (as rumoured) tomorrow, the question turns to what should I be loading it up with. I'll have the £15 Play Store credit that I got for pre-ordering, plus probably a further £20 initially, although I could conceivably stretch a way further.

So, what are your recommended apps for me to purchase/download, preferably one for when I have WiFi signal and one for when that is unavailable?