You can add details of your time worked manually when creating your billable hours invoice. This can be done by adding text blocks on a new page to the invoice before you send it to your client. If you need to include these details, use the Time Tracker table to help you fill in these details.

The stopwatch isn't currently available on desktop, but you can manually enter the time worked as well as handle invoicing for your hours worked from your computer.

You can use the time tracker for other time management tasks (like tracking team member time in a project). If you use the time tracker for anything besides billable hours, you'll want to make sure the Billable checkbox is unchecked for those entries. Otherwise, they may get accidentally included in the invoice you send your client for the billable hours.