Track your time automatically and create timesheets and invoices effortlessly. Chrometa captures every minute of your time as you work on your PC and/or Mac. For more information, check out Chrometa.
Remember if you have questions or need assistance with Chrometa, this is not the best place to ask - this forum is for reviews and feedback only.
For general support, check out the Chrometa support centre or this page for information on connecting Chrometa to Xero.
Although I am a Xero user, I have not integrated the billing as it is not something my clients need.
My boss liked the Activity Detail I submitted with my invoice so much that she now includes a blurb in her sales pitch and proposal about how detailed and accurate we are with our time reporting.
I run Chrometa on the PC in my office, my Mac at home, and on my Android phone. It captures the time I spend on each device and syncs it up centrally for me in my main account.
I use Xero as the central source of my client list. Chrometa syncs up with this list, so that I can assign my time entries to the right client (or better yet let the rules do this for me) - and then I send the time entries back across to Xero as invoices.
Once you start keeping your time automatically you'll never go back to notes and timers!
EDIT: The review below this, from Dragos Ailiesei, says my claim is not true, because there are reports you can export. Unfortunately, the reports you can export are not very useful for billing. That is why Chrometa charges for the useful ones.
EDIT: Motivated by Dragos's response, I tried Chrometa again and they have indeed improved their reporting enormously. As this was the only thing making it useless, I am trying it again and so far it is looking good.