It lets you git clone, browse the repo history, visualize diffs using animated transitions and sync-fetches updates as they become available - it's pretty cool :-)
Although it's a paid app, the code for Agit itself is open-source under the GPL v3 licence and available at https://github.com/rtyley/agit - there's some good stuff in there! I'm particularly proud of the support for SSH - I defined a ssh-agent-like AIDL interface for use by other Android apps, which leaves the choice of implementation (eg. ConnectBot) open to the user, and lets any other permissioned app on the phone to use it to make SSH connections. This means that Agit doesn't need to actually manage or even store SSH keys itself, it just uses ConnectBot to sign the cryptographic challenges that the remote server sends it... it's an awesome symphony of cryptography and inter-process communication :-)
I've written a couple of pieces for the Guardian about the development of the app - the first one is an overview - the second tells the story of a strange little bug hidden away in the source code of Android itself, which nearly stopped Agit dead in it's tracks. The Android folks were really cool on that one -the patch got accepted into Honeycomb.