I have used Airnav Pro and don't like it - there's a lot of room for improvement in terms of user-friendliness and speed. It's damn slow, at least on iPad 1.
Foreflight is better, but it only has charts for the US. I'd love to see a european version. My only caveat is map-scaling. On a paper chart the scale is obviously fixed and you can tell in a glance how far you are from eg. a city, airport etc. On the Ipad you can zoom the map in an out as you like, but there's no reference scale and you can't tell how many miles/klicks one 1nch on the screen represents. Minor thing, but IMHO it renders the VFR charts useless for pilotage/dead reckoning. But a good app after all, if not a bit too expensive.
Logten Pro is a good logbook, but again: I need two separate logs (one for planks, another for helis and actually a third one for gliders) - this can't be done on the iPad version (the PC version supports multiple logs). Also, printing your flights doesn't work too well. But again, not a bad app.
Another one I use is iBal - a special app designed for helicopter W&B calculations. No squawks here, it's worth the 7€ it cost.
Have used also some other apps but they weren't too good. Generally there's quite lot of aviation-related stuff in the App Store, but most is worthless...
Cheers!
Stuck
(Sent from iPad
)
P.S. Try Good Reader. Not exactly an aviation app, but it's great for downloading/storing/reading pdf files. I have all my manuals there and love it. Also used it for displaying approach charts and it worked well...