You are able to track duty times easily on Simply Log. Here’s how you can do that.
To “join up” or “chain” up multiple flights into the same duty, you just need to leave the “Duty End Time” blank on the first sector in your duty, as such.

When you are ready to end the duty, just make sure the “Duty End Time” is filled up appropriately. To calculate the “Duty Time”, just click on “End and Calculate Duty”.

You can also use this “chain” duties that involve more than 2 legs. For example, in a 4 sector day, just leave Duty Start Time and Duty End Times for the sectors that are in the middle blank. (for example, in a 4 sector day, leave duties in the middle are sectors 2 and 3).
The following screenshots show the Duty Times section for a middle sector.

When the duty ends, just enter the “Duty End Time” and click “End and Calculate Duty”. Simply Log would intelligently inherit the “Duty Start Time” from the first sector.
You don’t have to manually enter the “Duty End Time”. Simply Log can calculate the “Duty End Time” for you intelligently based on your “Arrival Time”.
To do that, you must ensure that the “Arrival to Sign-off” field is set in Simply Log’s “Settings”.

At the end of your duty, after entering the “Arrival Time” (in this example arrival time is 0452),

Tap on “End and Calculate Duty”. The blank “Duty End Time” would be calculated for you (arrival time 0452 + 30 minutes as defined in Settings), along with the “Duty Time”.

If you don’t want to accept 0522 as the “Duty End Time”, because it is a different kind of Duty where the Duty End Time doesn’t conform to the usual Arrival to Sign-Off default, you can manually key in a “Duty End Time”, tap on “End and Calculate Duty”, and the app would use your manually entered “Duty End Time” to calculate the “Duty Time”
