Penny - Penny is a personal finance app that takes the pain out of keeping track of your finances.
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!
Monarch - Social media sharing plugin for WordPress
Kittysplit - The easiest way of sharing costs with a group of friends
Spendee - See where your money goes
ihatemoney - Manage your shared expenses, easily