While running digital campaigns in facebook for Tootle (a ride sharing application launched in 2017 inside Kathmandu Valley), we incorporated facebook sdk in the app later than we launched the app in google playstore.
However, as we started tracking the app analytics from both facebook and google, there was a difference seen. The number of total installs in facebook and google did not match.
This was a curious case for us to solve since it was the very beginning of digital campaigns for us.
Unfolding the curious case
As mentioned earlier, we had incorporated facebook sdk later than we launched the app in google playstore (here lets just assume a date – 24th May 2017). Facebook considers install data only from this date (The last 28 days in facebook basically counts only these.) Before this date, facebook does not have the history of the installs and uninstalls which is why it might recount the installs that are not unique.
Unique installs – install count of users who installed the app on one or more of their devices for the first time in a selected time range.
Since, facebook has no uninstall data upto 24th May 2017, any installs after this date is counted as new or unique installs.
But Google has this data from the beginning. The last 30 days in google are the actual last 30 days. Also, it identifies “Unique” installs because it has the history of uninstalls. So, it does not recount installs of people who had previously installed the app but they uninstalled it for some reason and then reinstalled it.
Therefore in Facebook, the installs number might have been recounted regardless of the history hence the number of installs in Facebook was more than Google.
This might change as the last 30 days count remains same for both Google and Facebook.
However, even after the last 30 days count remains same, a number of other factors might come in play which could still make the number of installs appear different in Facebook and Google. Those are:
*If very old users before the date of 24th May 2017 install again.
*Google identifies unique user based on google account information.
*Facebook identifies unique user based on device id and not facebook id.