Pop the Lock is a high score chaser, but instead of accumulating points you spend every attempt counting down from your previous high score to zero (whereupon the 'lock' 'pops'.)
Aside from this little twist on the high score-chasing formula, Pop the Lock has a mechanic that's both new and familiar. A marker sweeps around a dial, and you have to tap the screen while it's over a yellow dot. If you succeed, the marker changes direction.
That's it. The gameplay is simple, and the graphics are almost insultingly ugly, but Pop the Lock is still a challenging casual time-waster with responsive controls and a gameplay mechanic that you probably haven't seen in exactly this incarnation before.