How many devices don't run Google Play I've recently integrated AdMob into my app.  AdMob requires Google Play Services, which requires the Google Play app.

How many devices do not have Google Play available?  I'm worried about losing potential users.
According the google's developer page here, google play is not required for AdMob to work.

From the Site:


  The Google Play services library supports even devices that don't have the Google Play store. To update such devices, download and bundle the latest Google Play services SDK; then relaunch your apps to propagate updates to your users. Devices that do have the Google Play store are automatically updated to the latest version.


There's also an answer here which explains that Google Play Services is not required to be able to have ads served to android devices. If Google Play Services is not on the device, the version you compile with your app will fetch the ads instead.