The solutions below are generally geared towards the latest Android version bugs, but some of them will be perisstant bugs from a slightly older version of Android, like Android 5.0 Lollipop. Generally speaking, the solutions will work no matter which version the problems appear in. But keep in mind that some bugs have been patched in later Android releases, so always make sure you have the latest firmware available for your device. To check, go to Settings > About phone > Software update.
Wi-Fi and Connectivity issues
This tends to occur on every single Android update ever. For every phone. Every time. The solutions are just as slap-dash and temporary as always too: toggle airplane mode on and off, forget and reconnect to your Wi-Fi network, toggle mobile data on and off, reboot your phone and play around with your Wi-Fi router.
You can also manually switch between 2.4 GHz and 5 GHz Wi-Fi bands, contact your cellular provider for assistance with Access Point Names or back up your whole device, clear the cache partition and then factory reset your Nexus 5 as a last resort. Some third-party apps have been blamed for this issue, and updates to include Lollipop compatibility have apparently solved the issues. But sadly, Wi-Fi connectivity issues are generally a modem problem that only Google can fix properly.
Random app crashing
Following the Nexus 5 Lollipop update, several readers reported random app crashes on their their device. The main culprit for app issues following an update is the app or system cache. If there’s one app in particular causing issues, just go to Settings > Apps and find the app in question. You can now clear that individual app’s cache.
If the problem persists, you can go one step further and uninstall and re-install the app, or restart your Nexus 5 in Fastboot Mode (turn it off, then press and hold Power and Volume Down, then use the volume rockers to highlight Recovery Mode) and clear the cache partition before rebooting.
Factory reset bug
Now this one sucked. This particular nastie meant that if you weren’t lucky you could get an unexpected factory reset simply because you tapped around on the lock screen of your Nexus 5 running Android 5.0 Lollipop. Fortunately this bug has been corrected in Android 5.0.1.
Battery drain issues
What do you know? A battery drain issue following an Android update! Whoever would have thunk it? This problem follows each Android update like day follows night. The simplest solution? Back up your apps and data, install the update and do a factory reset (or vice versa). Then restore your apps and data and enjoy a bug-free Lollipop experience.
If the battery sucking persists you can always disable certain power hungry apps or install a battery-monitoring app like Battery Doctor or Juice Defender to see where the problems lie. Sometimes you just need to update to the latest version of Google Play Services, do a quick reboot or factory reset to clear up the problems.
High RAM usage
Another performance bug that is relatively easy to fix is high RAM usage or sluggishness following the update. Again, like the random app crashes, the simplest solution to this problem is to go to Fastboot (turn your Nexus 5 off, then press and hold Power and Volume Down until you see the Fastboot menu, then use the volume buttons to highlight Recovery Mode and press Power to select it) and then wipe the cache partition
Another one to be corrected in the Android 5.0.1 update, this little annoyance meant that if you kept the flashlight on until it timed out, both the flashlight and the camera app wouldn’t work until you did a reboot. I wish I could say that Google got on top of this one quickly, but it was around way back in the developer preview.
No silent mode
There’s not much you can do about this lack-of-a-feature on the Lollipop side, but as promised previously, one of our awesome community members fromhas made a nice little silent mode toggle for your Nexus 5 called Silent Mode Lollipop. It’s simple and it works right from your notifications shade.