FLO is a scrypt based coin with quick transaction processing that introduces a useful new feature called 'transaction comments'. These transaction comments enable FLO to facilitate a number of unique applications and enhancements within the blockchain.
Credo is the token you earn when someone you don’t know sends you an unsolicited email. You can use the Credo you earn to send your own emails to people you don’t know, trade it for other currencies, or hold onto it as its power increases.