You need a permit or NYC Day Pass to play on the courts.
The tennis courts fill up quickly, especially on weekends.
Prepare to wait for a court during peak times.
I have been using it now for 3 months and it saves me so much research. Reduces the need to call and double check every time.
How did I not know these places existed?! Atly's scoring is a lifesaver, now I can finally find THE spot without wasting time Googling my life away.