What is the real montly retention?
GeneralVimes 293 posts

This is my first mobile game, EATERS  multitasking It was released more than 6 months ago. I get 2 new users every 3 days (and 2.1 uninstalls every 3 days) But I want to use it as a sample for a retention rate calculation. Here's what I see in Google Analytics in Cohort Analysis by day: Not much, eh? But If I select "by week", the picture changes: In "by day" the day 7 retention was 0%, but in "by week" the week1 retention is nonzero and equals 2.7%. Now, as you see, week4 retention is 1.35% Let's change the scale to "by month": Month1 retention is higher, 4.67%! So, what are the actual retention values for my game? This question is very interesting, because if viewed "by month", my another game (Cloudy Shaman  quick reaction) has the 1month retention bigget than 10% Although, in day wiew everything is not so bright: 
FGL_Dave 319 posts

Retention as viewed by publishers is Day 1, Day 7 and Day 30  and it's very precise. Starting with 20000 users on Day 0: If you have 10000 users on day 1, with 8000 on day 6, then suddenly for some reason you lose a bunch on day 7 (down to 2000), then it goes back up for day 8 (to 6000)... you Day 7 retention is exactly what it was on Day 7... 2000 (or, more precisely, 2000/20000 = 10%, as they are expressed as percentages of Day 0). Unfortunately, this 'snapshot' way of expressing retention is the industry standard, so any kind of average or sample doesn't really count for much! 
GeneralVimes 293 posts

Thank you Dave! I agree that this is standard, but the standards can be weird :) So, here goes another remark. If the game has hundreds thousands of installs, these fluctuations are impossible, but if it has only 100 users, the probability that the number of players on Day 8 will be higher than on Day 7 is quite significant. 
posted 20160723T05:08:4407:00
