Nice work, but certainly no replacement for PonyDebugger[0] with SuperDB[1]. Plus, they're both FOSS.
Sure, those don't have support for NSNotifications, but I've found it's best to avoid those as much as possible anyway (essentially like a super GOTO).
[0] https://github.com/square/PonyDebugger [1] http://shopify.github.io/superdb/