AffiliateWP - A powerful affiliate marketing solution for WordPress.
Splitwise - Splitwise is a free tool for friends and roommates to track bills and other shared expenses, so that everyone gets paid back. On the web, iPhone, and Android!
ReferralMagic - Turn your users and customers into referral magnets.
Dinngo - Splitting payments the fun and easy way
Echo - Golang HTTP server framework
/Tab - The simple way to split a bill among friends.