Timeview Icon

With Timeview you chose one or multiple calendars as a source and then you can add rules like "only events with duration greater than 2h and containing the word 'meeting'" allowing you to build your own statistics and insights about your calendar.

Try it for free (iPhone + iPad)
https://itunes.apple.com/WebObjects/MZStore.woa/wa/viewSoftware?id=1439197028&mt=8