Defending
When you start the game and are on defense, begin with a steal. Steal work well against opponents that are slower, want to shoot, or fake a shot. You do not have to do anything if they move to a side, but if they do, you still may have time to block them if they try to fake a shot first. Many players use patterns, especially when on offense. Some will try fake shots and moves to trick you, while others will always go to a side. It will be easy to guess their strategy after a few shots.
Upgrades
At level six you will unlock the Croc ball for purchase for 15 gold. Gold can be obtained by leveling up, playing in the higher courts and getting the gold shots, and connecting to Facebook.