Multi Timer is a Pebble watchapp that allows you to run several timers and stopwatches simultaneously.
Persistent Storage on the watch to remember your
timers, and even fakes the timers running in the background by calculating how
much time has elapsed since the app was last run and adding / removing this
amount of time from any running timers.
Some parts of the C and JS code are tested, and are run automatically using Travis CI.
Here is what the app looks like: