Maintenance release that bundles up many minor UI changes.

Changes to instruments:
Map - Weather overlays now show correctly over all aviation overlays
Chronograph - Fuel burn calculations now work when app is in the background

Performance improvements

Improved design and presentation

Further improved attitude algorithm, combining sensor inputs from gyro, GPS and accelerometer sensors for more reliable attitude indication

Much improved attitude algorithm using modified Kalman filtering
iPad compatibility

Minor bug fixes

Landscape orientation option
Choice of aviation or metric display units
Updated aviation database
Improved rate-of-turn and attitude indication

Added support for iPad 3G (with GPS)

-Continuous auto-calibration of the gyro sensors, resulting in much improved performance
-Communication frequencies for nearby airports
-Slip indicator
-Automatic flight timer
-Option to derive attitude from GPS instead of gyros

Support for iPhone 3GS, with attitude indicator derived from GPS (because there are no gyro sensors on the iPhone 3GS)

Improved auto-level algorithm and added all public US Airports to the database