Google's Gmail app has become the first stand-alone smartphone app to pass one billion installations on Android devices.
The milestone, announced by Sundar Pichai, Google's head of Android, was crossed sometime last week; the Google Play Store ranks apps by downloads in different ranges and the Gmail Android app ticked over into the one to five billion bracket.
The figure excludes updates, so there is no double counting when an update is issued. And the Google Play services app is disqualified from the counting, as it is required as part of the Google Play Store.
The Gmail app is installed by default on all Google Android devices as part of Google's licensing, which covers most of the Android software-powered tablets, smartphones and other devices available outside China. It is updated when the device connects to the Google Play store.
Amazon's Kindle Fire range of Android devices and Microsoft's Nokia X smartphones do not come with Gmail installed as default, nor is it possible to download the Gmail app through their app stores. Nor are there any figures for the number of downloads of the Gmail app for Apple's iPhone and iPad.
Several groups of apps, such as Outfit7's range of Talking Friends apps, have already passed the one billion downloads milestone, but no one individual app has been downloaded that many times on its own before. The Angry Birds collection of games broke one billion downloads in 2012.
Gmail's billion downloads reinforces data on how many Google-powered Android devices have been sold, with Google's executives saying that more than one billion Android device activations were passed last year.