Simple and small application allowing use flick gesture (from left to the right) to go back one level in Start Menu. Application has only 16kB footprint in memory. Best for explaining is simple animation: See?

How to make sure you use it right:
Beginning point and ending point must be less than 70px from itself on Y axis. Also, total distance between points must be larger than 110px plus difference on Y axis.
For programmers:
int Y1 = e.y;
int Y2 = TouchOrigin.y;
int YX = Y1 - Y2;
if (YX < 70 && (DistanceBetweenPoints(TouchOrigin, e) - YX) > 110)