Lollipop may be the latest version of the mobile OS developed by the search giant, but it's clearly not the most stable yet. In fact, the new and handsome iteration of Android has a memory leak bug that has some nasty effects.
On Android 5.0.1, the bug kills open apps and forces constant reloading of the home screen. On Google's Android Issue Tracker it's been revealed that a few Nexus devices are affected, such as the Nexus 7 (2013), Nexus 4, and Nexus 5.
In some cases the bug makes the Android system eat up to 1.2GB of RAM, whereas a normal value would be somewhere around 500MB. So this is a pretty big deal, and quite an annoying bug if you happen to encounter it.
The good news is that a fix may have been found, and it will be included in the next software update from Google. The only downside right now is that there's no indication as to when that will begin rolling out. It's unlikely that we'll see a specific update only addressing this issue, so the fix will make it to the next planned release - whichever that happens to be, and whenever that comes out.
So if you do suffer from the effects of this bug, you're still required to have some patience. Since Android 5.0.2 is already out for the Nexus 7 (2012), this bugfix will probably be released as part of Android 5.0.3.