I am tracking my Android app on Google Analytics. Why do I appear to have Macintosh users?

Question

The facts:

1. My company has developed an Android app.
2. My company has NOT developed an iOS version to this app in anyway.
3. I have created a Google Analytics account, opened a mobile app tracking ID, and connected it to my Android app using the SDK (this was not done by me, rather by our developer).
4. Our app launched and has some users according to both our Google Analytic's account and the Google Play Developer Console account.

In the Google Analytics if I examine the operating systems of my users my operaiting split is:

• Android - 91.69%
• Macintosh - 8.05% (Macintosh 10.10)
• iOS - 0.26% (iOS 8.1.2)

How is this possible? We haven't developed for iOS.

Answer 1

This is so-called referral spam. I won't go into details here as there're lots of good sources on the net about the issue(e.g. this, this and this one).
I've handled this issue like this:

1. Go to your app view in the Google Analytics.
2. Open the 'Admin' tab.
3. Click on 'View settings'.
4. There will be section called 'Bot Filtering', check the 'Exclude all hits from known bots and spiders' option.

From now on Google will remove the spam hits from their analytics. This solution has two issues, though:

1. Historical data will not be affected by this option, i.e. spam hits which were made in the past will remain in your data, Google will only filter your future hits.
2. Google promises to remove hits from known bots, which means that the time from the new bot appearance to the moment when it will be included in the Google filter list can be indefinitely long. I use this solution for the last week though and didn't find any new bots breaking through the filter.