Advanced Scoring Technique in 3 Draw Solitaire for iPhone
The secret (which is no real secret) is to finish in as few moves as possible, as fast as you can. If you find a hand you can finish in under 100 moves, replay it several times until you get the moves memorized without having to think about them. Then just keep practicing and watch your times decrease. To get none of the top 25 scores, you'll need a time of around 25 seconds (I'm not sure if this is till the case or not, but times under 25 seconds will not give you the bonus because the programmers assume they're glitches).
You can get to around 12000 by completing the game in about a minute. I've no idea how they get to 25000, unless playing a few seconds quicker is worth exponentially more points.