The great "flying" app for Android is
Oziexplorer.
You can get maps for every bit of the world for Ozi. On occassions they might not be, ahem, copyright free
but they come at the "right price".
On my first long flying trip (
UK to Crete) I flew all the way down there using Ozi and running aviation charts which I scanned myself. I wasn't taking any chances - I wanted to know where I was 100% of the time.
Nowadays, with an IR, it's
easier but if I was going VFR I would fly the same way.
The problem with the IOS platform for GA flying is that you are stuck with a small selection of official but variously crippled products, often you tear all your hair out trying to do something which should be really really trivially simple (like print to a PDF), or you jailbreak it and then you - for the most part - have to know what you are doing with messing about inside unix.
I have an Ipad2 which is great and does what Apple intended it to be used for brilliantly.