APPOK is the easiest chat in the world! You can only send "OK" and receive "OK".Created to make communication objective, which can be used on the go to make your life much easier.
For Example:
When you get home, send me an "OK"When you get to the train station send me an "OK"When you get to the Airport, send me an "OK"If you need a ride just send me an "OK"If you go to class, send me an "OK"