Android 5.0 deep-dive review: Exploring Lollipop's many layers

The notification panel, meanwhile -- what you see when you swipe down from the top of the screen anywhere in the OS -- no longer takes up the entire display; instead, it's a series of card-like rectangles presented in order of priority. The system ranks notifications automatically, but you can also set specific apps to always be high priority.

The notifications themselves work just like they have in the past: You can swipe down on them to expand them, tap to open them or swipe horizontally to dismiss them. An improved Quick Settings area is now built right into the main panel as well: You can get to it either by swiping down a second time, after you've opened the main pull-down menu, or by using a two-finger swipe-down gesture to jump to it directly.

Taking control of alerts

The most transformative shift in notifications comes with Lollipop's newly added controls over how and when alerts appear. If you're listening to audio and the device's screen is off, pressing either volume key will only raise or lower the volume. If the screen is on, however -- regardless of what you're doing -- pressing either volume key will bring up a panel on which you see the volume (of the ringer or audio, depending on what you're doing) along with the new notification controls.

You can then touch the notification controls to adjust them. They give you the option to toggle between a normal notification mode, a priority-only notification mode and a mode in which no notifications are delivered.

If you select either of the latter two, you're then given the choice to stay in that mode indefinitely or to set a specific amount of time for it to last. Think of it as a "do not disturb" option with the ability either to go fully silent or to allow certain high-priority interruptions through. By default, a high-priority notification includes any alarm, event or reminder; you can expand it to include calls and messages as well -- either from anyone or from specifically approved contacts -- and you can whitelist entire apps so their notifications are always allowed through.

You can also define recurring periods of time when your phone will automatically shift into priority-only mode -- if, for example, you want to keep your phone quiet except for emergency calls or messages overnight.

All in all, the system is powerful but somewhat complex, with lots of settings in different places. Some of it is a little confusing, too, like the fact that the only way to silence your phone in Lollipop is to select the mode in which no notifications are delivered; simply turning the volume down all the way will put your device in a vibrate-only state but won't set it to silent.

If you take the time to learn the system and figure out its nuances, it has a lot of potential -- but I do worry it'll be a bit overwhelming at first, particularly for casual users.

Multilayered multitasking

App switching has always been one of Android's strengths -- and with Lollipop, the way you multitask gains even more muscle.

Lollipop's Recent Apps command brings a whole new look to multitasking on phones and tablets. When you tap the Recent Apps button -- the square icon directly to the right of the Home key -- you're now presented with a series of large cards, each of which contains a live thumbnail of a recently used app or process. You can scroll through them and tap one to quickly jump between tasks.

There's a lot more going on here than initially meets the eye, though -- namely the fact that Lollipop's Recent Apps tool splits apps apart into numerous standalone pieces, all of which appear individually in the list.

It's a strange concept to wrap your head around, so let me provide a couple of examples. Say you start up Google Drive and open a document to edit within the app. If you tap the Recent Apps key after that, you'll see two new cards -- one for Drive and one for the document itself. So you can jump directly to either step.

Similarly, if you open Gmail and then start to compose a new message, you'll see a card in the Recent Apps list for both Gmail itself and for the individual message.

The weirdest one for me is Chrome, where instead of switching between tabs within the browser itself, every tab now shows up as an individual card within the Recent Apps list and you use it to move between them. (That one's actually optional -- for now at least: There's a setting within Chrome that allows you to disable it and stick with a more traditional browser-based tab management setup, if you prefer.)

The goal is to make multitasking more robust: In addition to being able to switch between Gmail and Drive, you can now switch between your inbox and the message you're composing or your file list and the document you're editing. In those sorts of scenarios, the newly expanded approach makes a lot of sense.

But like the notification control system, it can be somewhat confusing in practice. The Recent Apps list quickly turns into an enormous mess of overlapping items that's more overwhelming than useful. On my Nexus 6 review unit right now, there are 60 cards in my Recent Apps list. Sixty cards! Twenty-two of them are various instances of a Google search process -- either a search I'd completed or a blank search screen from the Google app. What good is that going to do me? And how am I supposed to navigate the Recent Apps list effectively with all that silliness cluttering it up?

Part of the problem is that too many processes are being split apart and saved as their own cards -- like all those blank Google search prompts I'm seeing. And part of the problem is that the list never seems to clear itself, even when you turn the device off, so it just keeps growing longer and longer to the point where it becomes unmanageable and counterproductive.

(You can swipe away items one by one to dismiss them -- but that isn't really a scalable solution, and you as the user shouldn't have to worry about playing custodian throughout the day.)

In addition, the breaking apart of in-app processes occasionally leads to commands not working as they should. I'll use the Google Drive situation as an example: Normally, if you open a document from Drive, you can then tap the left-facing arrow at the top-left of the screen to go back into your main file list. If you use the Recent Apps list to jump into an already opened Drive document, however, and then tap that same arrow, you're dumped out onto your home screen -- since the process was separated from the app, the "back" function no longer works as you'd expect.

All considered, the new multitasking system is one of those things that's great in theory but not quite there yet in reality. It's also surprising that Android still doesn't include any native system for viewing multiple apps on-screen at the same time, as we've seen some third-party manufacturers offer. While that's not something most folks would likely use too often, there are certainly times when it'd be handy -- like when you want to continue playing a video while answering a text or actively reference a document while composing an email.

Voice control

One of Lollipop's most noteworthy additions is support for always-listening voice control, much like what we've seen on Motorola's recent devices.

If your device has the hardware to support it -- and if your manufacturer opts to enable the feature -- you can now wake a phone or tablet and give it commands by saying "Okay, Google," even when the screen is off.

As you can imagine, there are plenty of occasions when that can be useful -- like when you want to send a text while driving or get a quick answer to a question while your phone's out of reach. The system is a few seconds faster than Motorola's, since it interfaces directly with the Google Search app without any third-party intermediary, but it's also less robust in a couple of ways.

First, while Lollipop's voice control can be trained to recognize and respond only to your voice -- a feature that actually works with the aid of Motorola's technology -- it doesn't allow you to set your own custom launch phrase, as Motorola's newest version does. That becomes an issue when you have multiple devices nearby: If I say "Okay, Google" in my office right now, the Nexus 6 and Nexus 9 will both light up and start listening, as will my Android Wear watch (if it's awake). Given the nature of the system, there's no real way around that.

Second, the system lacks some of the more advanced voice commands that Motorola has built into its devices -- like those to snap a photo from afar or to launch a hands-free mode in which all incoming calls and texts are read aloud.

While it may not be quite at the level of Motorola's implementation, though, it's still an excellent addition and one that'll add a meaningful amount of value to a lot of devices. I do wish Google had made it easier to find -- the option is off by default and buried five layers deep within the "Language and Input" area of the system settings, where most users are never going to notice it -- but if you know it's there, it's well worth enabling.

All sorts of sharing

Just a few more features to cover before we wrap things up -- and they're all related to the subject of sharing.

The biggest is multiuser support, which gains a few new tricks with the Lollipop release. Multiuser support has actually been available for Android tablets since 2012, but with Lollipop, it spreads to phones as well. That means you can allow your significant other, child or friends to have their own separate home screens, apps, settings and data within a single device, which is a wonderful option to have.

With phones, you can choose whether secondary users will be able to make calls and send texts -- via your number -- or, in what seems like a more likely scenario, be limited to using the phone only as an Internet device.

(I should note that the feature has been pretty glitchy on my Nexus 6 review unit; I'm able to test the basic functionality, which works as promised, but the phone often acts erratically when I'm adding a secondary account or switching between accounts. This is pretty clearly the result of a bug and something I have to imagine will be fixed in short order -- Google is aware of the issue and has confirmed that the phone will be receiving a software update of some sort within the coming days -- but as of now, it does feel somewhat unfinished on the phone front.)

In addition to the full-on multiuser support, Lollipop offers a new "guest mode" that allows you to create a temporary space so that someone can use your device without signing in or gaining access to any of your stuff.

And if you want something a little less involved, Lollipop provides a third option called "screen pinning." Once you've enabled it in the system settings, you just tap the Recent Apps key and then tap a pushpin icon that appears on the most recent card in the list. That'll lock that app to your screen so that anyone using your phone can use that app and nothing else (which is most effective, of course, if you set a pattern, PIN or password to secure the device).

One final sharing-oriented feature that warrants a mention is an expanded version of Android Beam. In addition to being able to share links and contacts by touching two devices together back-to-back, as has been available in Android for quite some time, you can now share any type of file -- an image, a document or practically anything else imaginable -- simply by using the standard system Share command and then selecting "Android Beam" from the list of options. Once you've done that, you just tap your device to the back of another Android device and a wireless transfer will instantly begin.

Under-the-hood improvements

Whew -- lots to look forward to, right? But wait: There's more. You might not notice them right away, but Lollipop delivers some important improvements to the Android engine room that should bring a boost to both performance and stamina.

There's a new runtime, for one -- the system that allows apps to operate on your phone or tablet. The details get pretty technical, but what matters is that the revamped runtime is supposed to let apps run as much as four times faster than what was previously possible. Google says it'll pave the way for smoother graphics and animations as well (you know, like the ones peppered all throughout Lollipop) and will provide a better foundation for background services that don't bog things down.

Lollipop introduces support for 64-bit devices, too, and it has a host of enhancements aimed at increasing battery life and improving stamina. As part of those efforts, the OS now offers a battery saver mode that can scale back your device's horsepower and background data syncing to help you eke out an extra 90 minutes of use when your battery's low (similar to what many manufacturers have already been providing).

Bottom line

Google's Android 5.0 Lollipop release brings a fresh and attractive new look to the platform that makes it feel more polished and mature than ever.

In addition to all the aesthetic improvements, it introduces a number of new features that add meaningful value to the experience -- like a revamped and more customizable notifications system, expanded options for security and the ability to use always-listening voice control.

And there are all the under-the-hood improvements mentioned above. It's too soon to have perspective on how much any of those items will mean for day-to-day use, but they certainly seem to strengthen the software's core.

To be sure, Lollipop isn't perfect; for all of its graphical polish, some of its features still feel a little rough around the edges. But it's a brand new start for Android -- and by and large, it's an absolute pleasure to use.