While Android 5.1 has introduced a few new features and fixes, Nexus 5 users are still experiencing an issue that has plagued them since Android 5.0 Lollipop released. A now closed issue on the Android Open Source Project Issue Tracker confirms that an Android 5.1 memory leak still persists, most notably on the Nexus 5.
The memory leak causes system RAM to not release properly when apps are closed and after a couple days of use, users start to suffer from slower performance, crashing apps, home screen launcher taking noticeably longer to display, and other issues. The issue seems to be affecting devices that performed a clean install with Android 5.1 factory images as well as those who installed the OTA (over the air) update.
For now, the only fix is to restart your device when you experience this behaviour, which wipes the RAM and of course frees it all back up for use. While the bug required almost daily restarts in 5.0.1, I – and others – have noticed that you can use the Nexus 5 for a couple days before having to restart it, which is a small improvement but obviously still a major issue in Android.
An Android project member closed the thread stating that
This has been fixed internally. We do not currently have a timeline for public release.
So once again, Nexus users are waiting for an undisclosed date for a fix to be pushed out for an issue many users have been having since November of last year. Have you been hit by the memory leak issue? Let us know in the comments below, or on Google+, Twitter, or Facebook.Source: Android Open Source Project