A Please Call Me is one of the most useful things a South African phone can do. It's free, it works on an empty balance, and it tells someone you need them to call. The catch is the code: *140* on Vodacom and Telkom, *121* on MTN, *111* on Cell C, then the number, then a hash. Get one digit wrong and nothing happens.
Please Call Me SA turns that into a tap. It reads your network, shows which network each contact is on, and dials the right code for you.
Since then the app has grown a few extras people asked for: airtime requests, sending airtime and data to any SA number, a weekly leaderboard with an airtime prize, and leagues from Bronze to Diamond.
The core stays the same. Sending a Please Call Me never needs an account, airtime or data. Everything else is optional.