Excellent, for the most part. Just a few suggestions:
1) Best 2 of 3 sets in all tournaments except slams, where it should be best 3 of 5. Really not sure why this wasnt included from the beginning.
2) Add female players, including the option to make a female player in career mode.
3) Online multiplayer.
4) Redo your line calling. Ive had many a ball called out when almost half of the thing has cleared hit the line.
Excellent start and, with the tweaks listed above, it could be the perfect tennis game for iOS. It already blows every other tennis game out of the water as far as graphics and gameplay go.
HotWingsFTW about Cross Court Tennis 2