The Team App timer seems to calculate in 10 minute increments. Often the timer and the logged time are not the same. What agorithm is being used to take timer time and calculate logged time in each ten minute segment?
The 10 minutes segment is counted in your Work Diary and the client is charged for it as long as the screenshot is taken during that segment. Since the screenshots are taken at random time, they can be taken for example at 11:22 and then at 11:38. If you stop the tracker before the screenshot for that 10-minutes segment was taken, the whole segment will not be counted in your Work Diary even if you worked for a few minutes of that segment. But that also means that if you started the tracker toward the end of the 10-minutes segment, it will be counted in your Work Diary even if you worked only a few minutes of the segment.
I hope this information helps.
Just a followup with more details as I promised.
The 10 minute segment seems to be based on set time rather than relative time. So 2:00, 2:10, 2:20 etc. The screen shot can be taken anytime in this 10 minute period, this is why there can be more than 10 minutes between two shots. For example 2:03 (2:00-2:10 segment) and then 2:19 (2:10-2:20 segment) then again at 2:21 (2:20-2:30 segment).
Time is logged in 10 minute chunks, so even if the screen shot is taken within 2 minutes of start, that is logged as 10 minutes and billed to the client. For this reason, the actual tracked time will mostly differ from logged (paid time) so be careful and fair.
For hours worked (displayed on profile), the system rounds up or down the time using regular arithmetic. So 0:10 and 0:20 are rounded to 0 while 0:30, 0:40 and 0:50 are rounded to 1:00 hr. The 10 minute segments for each contract are added daily and then added to the total displayed at 00:00 GMT daily. So this value changes daily.
Contracts in progress are updated weekly though after payment is made @ 00:00 again. So additional hours worked on a contract are added then rounded to give a weekly total for that contract. I am yet to see a difference in time resulting from if I rounded each day first rather than each week. Only possibility of such a problem would be two 0:30 minute times - but that is why the week is summed first, since that is fair to the client.
Maximum margin of error for the system, for you not being paid is -19:59 * $ Rate. So be careful when hitting the stop button on the time tracker.