Start picks a client and begins counting. Pause it, resume it, or move it to a different client mid-session. Stop it and the time is logged against that client's balance.
Every logged entry takes a description. That is not optional, and it is the difference between an invoice line that reads "consulting, 12 hours" and one that reads like an account of what happened.
Starting from a to-do
A to-do can be handed straight to the timer, which fills in the client and the description for you. The thing you planned becomes the label on the hour you billed.
Time you forgot to time
Log time records hours without having run the clock — the phone call, the thing you fixed before you sat down, yesterday. Same fields: how long, and what it was for.
Today
A running bar shows the time logged today, and a daily goal if you set one. Today's log opens the entries themselves, which is the question most people have at the end of a day: not how long, but on what.
Discarding
A timer left running by accident can be discarded rather than logged. It does not reach anyone's balance.