Strike and Dip turns your iPhone into a pocket transit. Take strike & dip measurements, bearings, plunge, and all that geological goodness, while simultaneously getting your latitude, longitude, and elevation. Choose between azimuth and quadrant formats for bearings, and three formats for coordinates.
To measure strike, just hold the edge against a dipping surface and and handy yellow triangles tell you how to level your iPhone. To measure dip, turn the iPhone up on its side in the direction of dip. Strike and dip will highlight in green when you have an accurate measurement. Position and elevation also turn green when you've got a good reading.
Compass features require iPhone 3GS