For Windows:

c:\Users\<username>\AppData\Local\inTennis

e.g. c:\Users\Mepong\AppData\Local\inTennis (where “Mepong” is the username)

For Mac:

~/Library/inTennis

e.g. /Users/mark/Library/inTennis/inTennis.app (where “mark” is the username)