Launch the application. While the application is loading you see the splash screen with the OSMTrack logo and the address of this website. As soon as the application is started, you are presented with the app's main screen:
Part 1: Starting
If you are starting for the first time, the system will ask you whether the application is allowed to use your current location. Press OK.
In a short time a first guess of your current location shall appear. The current location is represented by a purple quadrilateral in the center of the screen. The acute angle of the quadrilateral always shows upwards and corresponds to the direction of movement as estimated by the GPS, i.e. the track view rotates around the current location if a direction change has been detected. The precision of the direction estimation directly depends on your speed: if you move very slow it can be the case that the direction estimates are too imprecise and the direction is set to the default value - north. The faster you move, the more precise your direction estimation is and the faster it gets to the correct value.
At the beginning the current location will be very inaccurate, the blue circle visualises how large the inaccuracy is, the numerical value of the inaccuracy is written below the current location mark. The location inaccuracy will decrease as soon as a better GPS fix will be available.
You can pan and zoom the track view as usual by using swipe and pinch gestures. The current scale is visualized in the bottom-left corner of the view. To return to the original scale (1 pixel = 1 meter) and center on your current location double tap on the screen.
When you have logged some tracks (or there already were multiple tracks on your iPhone before the current update) points of those tracks are drawn on the display providing you with a basic "map" of the already logged paths.
The compass at the top-right corner of the screen provides a direction to the north relative to your current movement direction. It is based only on GPS and doesn't use the integrated compass of iPhone 3Gs (i.e. it shows the same direction independently from how the iPhone itself is oriented).