Joinery.nyc - Connect with outgoing tenants instead of brokers.
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!
PadMapper - A free tool to help you find an apartment or sublet to rent.
/Tab - The simple way to split a bill among friends.
Rentlogic - Apartment building grades based on facts, not opinions
EquiTable - Split the bill fairly