As Android 5.0 Lollipop is still rolling out to top 2014 smartphones on all carriers in the U.S., Google has already updated its own Nexus line with an even newer Lollipop, Android 5.1. For those just getting up to speed with Android 5.0 Lollipop, here's what to look forward to with the next incremental upgrade.

We got our hands on the Nexus 6 -- the flagship smartphone from 2014 that introduced Android Lollipop -- and managed to bring it up to speed with Android 5.1 Lollipop ahead of the carrier's schedule, in order to hunt for any big differences in the new Google OS.

(Photo : Robert Schoon)

Comparing it to the Moto X 2014 running Android 5.0.2 (which technically isn't pure Android, but given Motorola's minimal changes, it's pretty close), here are the biggest changes coming in Android 5.1.

System Sound and Notifications Settings

Google has fixed a few annoying bugs in the system sound settings, as well as tweaking Lollipop's new Priority Mode and No Interruptions Mode to make the options easier to understand.

Most importantly (though ironically, this is a very small change), you can now access the notifications settings float window while watching videos or listening to music by clicking on the bell icon on the right to expand the menu beyond the volume slider. Previously, there was no way to keep media playing while changing these settings, and that was just dumb.

There's still no mute or silent mode for pure Android 5.1 Lollipop, but there are some nice tweaks to the No Interruptions and Priority modes that almost make up for it.

The options for "None," "Priority" and "All" now come with icons, making it a little more intuitive for Android non-pros. Also, when you set the phone to Priority or No Interruptions for a specific time period, the menu will automatically show you what time those modes will expire.

Finally, you now have an option to let the next alarm turn off your "Downtime" -- the setting for recurring Priority or No Interruptions modes.

Quick Settings: A Little More Lively, Useful

The quick settings panel (the menu reached by a two-finger or double swipe of the notifications panel) has been tweaked to make changing data connections easier.

Instead of simply having the WiFi and Bluetooth options toggle on and off, Google has added dropdown arrows so you can quickly change WiFi or Bluetooth connections without having to go to Settings. This is one of those small changes that results in a lot of time saved over the course of your week, especially if you hop between wireless networks several times in the course of your day.

The other change to quick settings is cosmetic but nice: Google added animations to toggling settings like auto-rotate, as well as a few other nooks and crannies throughout the system.

Security Enhancements

A lot like Apple's Activation Lock, Android 5.1 Lollipop comes with a feature called "Device Protection." The setting, when enabled, makes your Android device useless to a thief, by requiring the right Google login credentials to unlock the phone -- even after a factory reset.

Though only available on the Nexus 6 and Nexus 9 at the moment, expect new Android phones running Android 5.1 right out of the box to take advantage of the theft-deterrent software -- unless, like Samsung, they already have their own version of a smartphone theft-lock.

Screen Pinning Makes More Sense

We thought one of the coolest features of Android 5.0 Lollipop was Screen Pinning (read our hands-on Lollipop review for more details). It's a bit of a security blanket that pins one app to the screen, allowing you to share your phone with a friend (or toddler) while specifying the only way your pocket computer can be used at the moment.

Now it's a little more intuitive for Android newbies, and shows users exactly what buttons to hit to get out of the "pinned" mode when you set it up -- and it's easier to find in Settings' Security sub-menu.

Native HD Voice Calling & Dual-SIM Support

High definition voice calling is now native for Lollipop phones with Android 5.1, if it's supported by the carrier, so calls will sound a lot clearer once you upgrade. Reportedly, only the Nexus 6 on T-Mobile and Verizon will have the feature at first, but expect more devices running Android L 5.1 on those carriers to include the feature going forward.

Android 5.1 also includes native support for dual-SIM configurations. This doesn't matter much for the U.S. market, but it's a step up for Android internationally. Finally, Google has new APIs for developers in Android 5.1 that makes it easier to create apps that take advantage of dual-SIM phones.

Other Changes

There are a handful of other, more behind-the-scene changes in Android 5.1 like the option to hide notifications in the notifications screen without dismissing them. Most important are the bug fixes, including by most accounts, the majority of Contacts freezing problems and the dreaded memory leak issue.

If only Google would add a quick setting toggle for voice recognition. Maybe by Android 5.2.

Are you anticipating Android 5.1 Lollipop, or are you still waiting for 5.0? What changes would you like to see in the next Android update? Let us know in the comments below!

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