Ollert - Learn what your Trello boards aren't telling you
SmallDevTools - Handy developer tools with a delightful interface
Vacation Tracker - The easiest way to track your team’s vacations and days off.
LaunchKit - Open Source - A popular suite of developer tools, now 100% open source.
Punchtime - Nifty time tracking for Trello users and teams
TextLab - TextLab is the fastest way to format, prettify, transform, hash, encode, and decode your data instantly!