Let the update automatically try again. If an update starts downloading and doesn't finish, your device will automatically try again over the next few days. When it tries again, you'll get a notification. Open the notification and tap the update action. Update Android version for security updates
Sep 07, 2015 Android Lollipop release date and features: more phones Oct 16, 2014 Lollipop, new, even BIGGER, update!!! - Android Forums Jul 02, 2015 Android version history - Wikipedia Android 1.5 Cupcake (API 3) ; On April 27, 2009, the Android 1.5 update was released, based on Linux kernel 2.6.27. This was the first release to officially use a codename based on a dessert item ("Cupcake"), a theme used for all releases until Android Pie, with Android 10 using a number-only system. The update included several new features and UI amendments:
Android Developers Blog: What's New in Android 5.0 Lollipop
Android 5.1, an updated version of Lollipop, was unveiled in February 2015 as part of the Indonesian launch of Android One, and is preloaded on Android One devices sold in Indonesia and the Philippines. Google officially announced 5.1 by releasing updates for existing devices on March 9, 2015. Android Developers Blog: What's New in Android 5.0 Lollipop Oct 20, 2014
Jun 03, 2015
What’s the Latest Version of Android? Nov 15, 2019 Check & update your Android version - Android Help