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!
Circular Design Guide - Toolkit that brings design thinking full circle
Splittable - Shared living made simple
Design for Startup - Everything about design for startups
EquiTable - Split the bill fairly
Text A Coder - Send a text, get a developer and project manager instantly