title: Determine if an user is using a feature for a time period
body: <p>I have an email application where you can see mails in threads view or mail view. I would like to provide information to the business whether users are using mail client with threads view or mail view. The problem is mail application can run for days and weeks before any user interaction. if I send GA event when the user switch to thread/mail view that event can be registered for the day it was sent (lets say it is 1st of January) but the client can keep looking at the mail list for a month. Lets say business guys make a query for the last week of January the event won't be counted and they won't know there was an active user.</p>
  <p>My solution is to send this event every day by some time service which will monitor for day changes but I think there could be better solution to this problem and you can tell me about it</p>