Get a programmatical notification when an address receives a transaction
Polling bitcoind is superior to any other alternatives as there is zero lag, your operations don't depend on a 3rd party SPOF service, etc. 

A fresh incoming payment is also an outspent output, so calling bitcoin-cli listunspent 6 9999999 "[\"localAddressInQuestion\"]" will provide you with the exact unspent amount for this address only. Replace 6 with any number you wish to set as the confirmation threshold or make it 0 to get the unconfirmed payments as well.