It has some advanced features like estimating the time spent on each line item based on number of commits or number of source changes.
For more accurate invoicing, you would utilize an app like TimeSink to record your computer's activities and then BBNW can cross reference that time spent with your git commits and figure out the billed activity that way.
Nonetheless, absolutely great job on the implementation! I had no idea anyone else was working on the same problem. If you're in the Bay area, I'd love to collaborate.
Please check it out and if you like it, vote for us.
Thanks