Keeping track of time in an application is almost as important as recording the measured levels. Using a timer makes keeping track of time elapsed just that much easier.

Stopwatches — These small, handheld timers are particularly useful for work in the field. However, their pure ease of use makes them fit into any application.
Desktop — Choose a desktop timer for a little more versatility than is afforded by a stopwatch. Select from a variety of units to best suit your application.