If you want stats on the duration of anything you do or the time between you do it, then Ekde is the right tool.
It is perfect for keeping track of
* time spend on multiple jobs
* time between lapses
* frequency and duration of activities
* or, in general, anything that takes time
and see if and how it changes over time.
Features:
* customize everything trackable
* track (repeating) episodes of arbitrary length
* add notes wherever you want to
* get stats on episodes
* get stats on the time between episodes
* visualize the data as charts
* visualize timeline with multiple tracked items
* all data is exportable
* data is only stored locally - no one else has access to it
* lots of themes