This is probably the best idea we have seen for an aviation app. AirspaceAVOID provides protection for pilots against an airspace infringement. It uses GPS data to plot your position, altitude, speed and heading, and it knows where all the controlled, prohibited and restricted airspace is located in your vicinity.
If you get within 2 minutes of restricted zones, AirspaceAVOID will alert you by sight and sound, giving you the opportunity to change track and avoid that embarrassing radio call no pilot wants to hear.
Currently supported Regions are Europe, USA, Canada, Australia and New Zealand.
For increased accuracy you should seriously consider the Bad Elf GPS Receiver which will boost your GPS signal making this great app the ultimate, and cheapest safety tool.