Android 5.0 Lollipop made its debut on the Nexus 9, Google's new tablet, and the Nexus 6, its latest smartphone.

With Android 5.0 comes a range of changes that feel like a repositioning of Android, rather than a huge bump in forward-facing features.

We've been living with Android 5.0 Lollipop on the Nexus 9 for some months and more recently on the Nexus 6, for a full and complete updated review of this updated version of Google's mobile OS.

This is your next version of Android and you're going to want it, so pay attention. 

The biggest change, the immediate difference you'll see, in Android 5.0 Lollipop is the new design language. Called "material design", it's this that makes Android feel like a bigger update than previous iterations.

There's fundamental change in how Android is presented and how the design is positioned across a range of native apps. As Google has split just about everything out, material design isn't the exclusive preserve of Lollipop: Play Music, Chrome, Newsstand, Gmail, Calendar and other core Android apps have all had the design makeover and have rolled out to a wider audience, so even those without the OS update get some of the visuals.

Android Lollipop review

Material design makes a more aggressive use of colour than previously. It uses bold colours and edge-to-edge imagery, very much a reflection of the changing trends online as much as anything else. Things are flatter, icons have been revised, lists and switches simplified, leading to a more modern look.

But material design isn't simply about making Android look different. It's an OS-wide housekeeping job, looking to bring refinement across all the core areas of your device and make your interactions with it nicer.

Android Lollipop review

KitKit used layers in animations, with the apps tray opening as a sort of zoom to the centre, and new pages rising up from behind as you swipe through. Lollipop has an exaggerated opening animation from the apps tray button, but then presents apps in pages on a white background.

These pages are much more cohesive with the use of cards elsewhere in Lollipop, and previously in KitKat. Most easily recognised from Google Now, there's a better card-style presentation of notifications too.

In both cases - apps tray and notifications - shading and dark backgrounds are gone, in favour of a brighter, whiter, design. That's true of the settings menu too - dark is out and light is in.

The animations are more fluid and consistent too. Apps open from the bottom, sliding up as if everything is stored just off the bottom of your device. They close the same way, dropping down to return you to the homepage. Sharing pops up from the bottom too, and the hop from one app to another is wonderfully slick.

Android Lollipop review

The result, fitting with material design, is that those main UI interactions have more impact. There's more colour, more vibrancy and a more modern look. Material design evolves Android into an OS that feels more consistent, a better foundation to visually carry it forward. Importantly, stock Android is now much more refined, and those third-party skins will be faced with a real dilemma of how much to change.

But it's not entirely consistent. The use of colour varies and the interplay with the notification bar is different. Open Gmail, which carries a red colouration, and your notification bar is red too. Not the same red, it's a few shades darker. The same applies when you open the Docs app, but in this case it's blue, again, a few shades darker. That can only be by design, which is fair enough.

However open Keep - which has a yellow colour - and the notifications bar is black, open Slides and it's yellow. It's black in Google Maps, black in the Photos app and black in Hangouts. There's no reason we can see why these core apps don't follow the pattern of other apps. It's also weird that Google Earth flows behind the notifications bar and Google Maps doesn't - two apps very closely aligned, but behaving differently.

Android 5.0 review

Hopefully some of these small details will be ironed out for a better overall experience, it might just be that certain apps are still awaiting updates.

We've talked about the change in design around the homescreen, but the principle is very much as it was in Android 4.4 KitKat. Google Now is the default homescreen (there's support for other launchers as before) and it behaves much as it did previously.

Google Now has had a design makeover however, with some cards having coloured top bars that make them more distinctive. They take up a little more space, but where the Nexus 10 offered a single column of Google Now cards in portrait, it's now double on the NExus 9, so you're getting more information, if you have any. On the Nexus 6, it remains a single column.

Android Lollipop review

Control of the Google Now/Search app settings is better placed too, with a menu you can open from the new icon in the Google search bar. This opens a familiar sidebar (which you'll recognise from things like the Play Store) letting you switch Google accounts, but importantly giving direct access to customise and settings options.

It's much more accessible than scrolling to the bottom of Google Now and much more consistent with other core apps.

Android Lollipop also supports the "Ok Google" command when the screen is off. At the moment it only appears to work with US English and we couldn't get it to go when we changed language, so it's something we'll have to watch - essentially it should mean you can talk to your phone without having to wake it up first.

With gestures becoming more commonplace, Android now supports double tap to wake, as long as you have the hardware. It's enabled on the Nexus 9, but not on the Nexus 6, which seems an odd choice, as we're sure that all the hardware is in place.

It's a nice option to have at the stock level, although it's already in place on many Android devices like the LG G3 and HTC One (M8). Here it works exactly the same way. You tap, the screen wakes up, and you're good to go, which is really useful when you're using a device one handed.

Android Lollipop review

You also still have support for the single finger swipe and two finger swipes. One swipe down pulls your notifications with it. However, as the Quick Settings and notifications are now on the same pane in Lollipop, a two finger swipe will bring down the lot in one go.

If you use a single finger swipe, you'd then have to swipe again to access the Quick Settings.

Notifications, for us, are the darling of Android. They're the thing (along with the supremely easy sharing) that make Android stand above rivals. As we've said, there's a refreshed design making things brighter and more distinct than previously.

Increased use of colour makes notifications even more compelling, with app icons giving visual identifiers for what you're looking at. You can still expand with a pinch and take direct actions as you could before, like snooze, reply or get directions from calendar reminders.

Android Lollipop review

You also now have lockscreen notifications. They existed before as a third-party option, but now they are a native Android feature. You lose the lockscreen widgets in the process, but we're not too sad about that. Lockscreen notifications are much more useful. 

You get plenty of control too, with the option to show nothing, to hide sensitive information (the sender and content), as well as showing all, which we suspect many will opt for. When you have a notification on the lockscreen, a double tap will open that app up, so you go straight to it, or via security if you've enabled those features.

Importantly, there's now an area to control notifications in the settings, and a new way of managing how app notifications appear. This, perhaps, borrows from iOS in grouping everything together to control notification behaviours at the top level, letting you dictate which app notifications are a priority, and letting you block notifications for an app entirely.

Setting priority apps is how you'll manage notification behaviour, because you can now define when you're interrupted and when you're not. You can elect to allow priority apps to always interrupt you. You can also define times you don't want to be interrupted, setting days and hours for quiet time.

Android 5.0 review

Setting an app as a priority app will also bump the notification to the top of the list. That might be nice for notification management, although how many notifications types do you normally have? We rarely have so many that we miss something important.

Notification management, however, also still sits in individual apps. For example, Twitter for Android still has the comprehensive notifications options it had before, there's just another way to govern behaviour overall. If you can't find the settings to cancel a notification, you now have a central way to do so.

Additionally, from the app notifications settings there's a link back to settings for Google's apps. It would be nice to see all apps plug into this central Android feature, but we doubt likes of Facebook will ever see the need. But it does mean for things like Gmail, Calendar or Google+, you can hop from one area of settings to the other easily.

There's also a handy pop-over notification. If you get a call or a message when you're doing something else, it appears at the top of the display so you can respond. That means you can reject a call without leaving what you're doing, or tap a reply to a text message without moving over to the Messenger app.

The volume controls have now had a tweak too. From here you can change the notifications/sound profile with a quick tap, selecting none, priority or all notifications. You can also define time periods for the change - indefinitely, or for up to 8 hours.

Android Lollipop review

You have to press the volume button to get this volume control to appear, but once you do, you can also tap the icon to switch to vibrate. Again, this has been a third party feature for ages (i.e., HTC, LG) and it's nice to see it here.

All we need now is the option to silence everything, as these volume controls are only for notifications. Media volume is separate, so you still have that situation where you've turned down the volume, you open up a video on YouTube and it blares out at full volume.

We're left wishing that Android would surface media volume control a little better, like Windows Phone 8.1 now does. Having a second slider for media volume wouldn't be too tricky and we'd prefer that to the current arrangement on stock Android where you either have to enter the settings menu, or you have to control the volume once the app or game is open.

Quick access to hardware controls is an important element for mobile devices. Android has long offered access to some controls, but it's never been as adept at the stock Android level as it has been on other devices.

You get many of the same options in Lollipop as you had previously in KitKat, but the welcome addition is brightness. You can bump the level up or down after a swipe, however the option for auto-brightness is in the settings menu. In most cases you can just leave it on, but bump the brightness up or down manually if you think it's not hitting the levels you want.

Android Lollipop review

The hardware controls also make Bluetooth and Wi-Fi control better. Previously it was a toggle - you'd hit the button and Wi-Fi would switch off. Now you have the network name underneath it, so you can tap that and switch networks quickly, rather than having to open the settings, then the Wi-Fi option. The same applies to Bluetooth.

The Wi-Fi icon will carry an exclamation mark if it's connected to a poor network and can't get online. We've found this when connected to a mobile hotspot - as you can tell that you've got no internet access - but we tried the same thing disconnecting our broadband router and didn't get that icon, so it's a little vague at present. You can also set which Wi-Fi networks are metered, i.e., when tethered, so that you get alerts about large downloads such as app updates.

You also have the "flashlight" option in Quick Settings, so it's just a swipe away. That should sound the death knell for torch apps, some of which have reportedly been snooping on users' activity. Opps.

Swiping into the Quick Settings also lets you tap through to the main settings menus and there's a search option here. That means that if you want to find encryption, for example, you just enter that to see the options. As voice is supported by the keyboard, you could just speak it too.

Multitasking has always been pretty good, but third party skins have often improved on this Android feature. For a long time on a large tablet, stock Android would give you a fairly small thumbnail. Lollipop changes it entirely, again for a card-style approach, rather like a Rolodex of recent apps.

Android Lollipop review

Tap the new button (a cleaner simpler square) and you'll pop into recent apps. You can flick up and down the selection and dive through to whatever you want to get back to. Apps can be swiped away or closed and it's all nice and slick.

It also fits the animation of opening apps, with you scrolling up and down. Again, we're right back to the feeling that all the apps are living off the bottom of the display, as the cards flick up when you hit the button.

There's also the option from Chrome to have browser tabs appear in Recent apps as individual tasks. We've found this makes it a little more difficult to quickly move from one tab to another, as they aren't as immediately accessible in Chrome itself - you have to tab recent apps and scroll through to the tab you want.

Battery is the biggest area of contention in modern devices and Android 5.0 Lollipop takes a couple of steps toward improving the battery performance. Some of this is under the skin, for example, the support for 64-bit hardware means access (potentially) to more power efficient components in the future.

But on a user level, there's a new power saver function. It's commonplace on third-party devices where Sony, Samsung, HTC, LG, et al., all offer some take on battery saving. Now there's a native option that throttles the power and reduces background action.

Android Lollipop review

It also makes a change to the UI that you can see. Rather than a just giving you a notification icon, it changes the background system bars (notifications and navigation) to orange. It's distinctly different, so there's no mistaking what's happened.

You can set battery saver to engage at 15 per cent battery, or 5 per cent battery, to hopefully extend the life until you can get back to a power supply. When you plug it in, power saver turns off again. Google says it gives you 90 minutes extra, which in the grand scheme of things perhaps isn't worth getting too excited about.

The battery saving mode is very much like HTC's implementation rather than the granular offering of Sony Mobile. It's also not the drastic extreme power saving option you now find on a number of devices, like the Samsung Galaxy S5. We suspect that Android's native power saver option will never see the light of day on many devices for this reason - it's not really noteworthy.

One thing that's very obvious when power saving mode engages is the processor throttling. If you're playing a game and draining the battery, you'll notice a distinct change performance when power saving mode engages.

You also get a predicted battery lifespan in the battery status page. Again, this isn't hugely advanced, as pretty much every other Android device offers that information. It's still a little irksome that there's no option to display battery percentage all the time, you still have to swipe down to see that information.

You'll also get a time to fully charged displayed at the bottom of your lockscreen, so you can see how much longer it needs to be plugged in for - but this doesn't appear straight away, it needs a little time to get going.

Android KitKat supported different user profiles, allowing multiple users of tablets, but now you can elect to have a proper Guest user.

That means you can open up your device for someone else to use and give them their own space, rather than having them snooping through your stuff. The guest can then do anything they like - log in to a Google account, make changes, install apps, without that affecting the device owner.

Android Lollipop review

From the lockscreen you get the option to log in as the guest user and that person can return to their session, or, if it's someone new, start from scratch again.

This all happens in parallel to proper permanent users, also supported as previously, letting you set up full or restricted profiles. The advantage of the guest option is that you can just give someone your tablet for a weekend and then just clear out the lot easily.

Switching users is very easy, as the person signed in appears both on the lockscreen and in the hardware shortcuts. All you have to do, for example, to switch over to a child profile, is tap the user picture and select who the new user is.

There's been a lot of talk about device security and data recently and Android 5.0 Lollipop brings in a couple of new features. First of all, your data is encrypted by default, whereas previously it was an option the user had to engage.

You then get the option to force password/code entry before the device starts. Like the KitKit encryption option, this means that if your device is restarted, someone will have to enter that code to get any access at all. Without it, you don't even get to the lockscreen, and your data should stay encrypted and secure. This is really a protection for those who have a device stolen.

But unlocking devices can also be a huge pain. What you really need is some way of letting your device sit in a safe state in the right conditions without having to fiddle with the settings each time ... that's where Smart Lock comes in.

Android Lollipop review

Smart Lock lets you give it a trusted face in addition to other security measures. If it recognises you it will unlock. If not, it presents the other lock option you selected. It's seamless too, so once you've set it up, as long as it recognises you you'll never notice that you're using it and no one else will know that it's using face recognition.

Face recognition has the same limitations as before - it doesn't work in the dark and this isn't some sort of magic CIA retina scanning, so it will potentially unlock with a decent picture of you. We've also found it to be a bit hit and miss and despite setting it up, 99 per cent of the time we need to enter a password too.

The second element of Smart Lock is really clever. This will let you assign trusted devices. That might be a Bluetooth device or an NFC tag. That means you can place an NFC tag somewhere and tap it to let your device know it's safe, and get rid of the lock.

Where this will really come in handy is in the car. When you're connected to your car's Bluetooth system, you really don't need to be fiddling with device security. Yes, when driving you shouldn't be fiddling with your phone, but we think this will be a popular feature, especially for those who have a docked phone streaming music, for example, or ad hoc navigation.

We won't dwell too much on apps, because many operate independently of the OS, having regular updates through Google Play.

Gmail has had a facelift, making it nicer to switch between multiple accounts and a much nicer environment overall: the new Gmail looks much more like a polished consumer app, and flushing out those greys is very welcome.

On tablets the layout is pretty much the same as it was before, only the labels/folders are hidden, opening up when you tap the button at the top. This opens a sidebar - very much like other native apps - and you'll also find the settings here too. Amongst those settings is the option to add accounts, supporting Yahoo, Exchange accounts and others, as the stock Mail app is now defunct.

There's now a floating compose button at the bottom, which sits in the same place as a similar button for in the new Calendars and Contacts apps, essentially elevating the main function so it's easy to access. You'll have already seen it in the latest Google Drive app for Android.

The power of the Gmail app shouldn't be underestimated. The attachment options offered by Android's universal file navigation make it very useful as you can essentially attach any file to an email and share it. Even better, however, is the option to reshare something you've been send. You can select an attachment on an email, you have the option to save it to Google Drive, or convert it to a PDF when sharing with someone else. All this happens within Gmail - long gone are the days of downloading an attachement, opening it in an other app, resaving a new version, then attaching it to an email.

Contacts is one of the things that typically third-party skins do a much better job with, but there has been some refinement in Lollipop, with more colour and a cleaner look. When you scroll up, the photo adopts the contact colour (which appears to be random) and it all nicely blends together. The Messenger app is the default SMS provider and we prefer it to Hangouts, especially if you don't want all the extras that Hangouts brings.

The Dialler works well enough, letting you start tapping in a number and suggestions rising from your contacts. We also like that incoming calls will be identified, so long as Google recognises the number. That gets rid of some of the anonymous calls that might appear, instead coming with logos and company names. It's not new, but it's not on many Android devices.

Calendar has some interesting options as you'll find "seasonal backgrounds" now offered. Pardon me? That's right, some of the weird backgrounds that appear in Android Wear have crept into the Lollipop calendar. Each month has an image to fit the season. There's also the option to turn it off in the menu, if you can't be bothered with the extra clutter.

Android Lollipop review

But one of the things we really like in Calendar (seasonal backgrounds we're nonplussed about) is backgrounds to certain events. A dentist appointment had a toothbrush, which is a nice touch, but even better is location maps, rather than just a link.

That means that if you've got accurate location in your calendar, you can tap on the event to see where you have to be on the map. It gets a little too clever, however, as one event we found pulled in a photo of the venue - less useful - and another event that had "breakfast" in the title as well as a location showed a graphic of a dinner setting - not useful at all.

There's also been a change to the keyboard, which is now simpler, cleaner, with a light or dark background. It's flatter, losing the individual key squares, for a design that matches the rest of Lollipop. This in now a theme option across Android devices, so everyone can get a taste of it.

There's a lot of Android 5.0 Lollipop that sits under the skin and doesn't result in something you'll immediately notice. There's enhanced handling of Bluetooth, with more efficient scanning for Bluetooth Low Energy (BLE) devices like sportsbands and Android Wear watches.

There's also better hand-off between Wi-Fi and cellular networks, meaning you should be able to smoothly move from one to the other and keep your conversation going on Skype or Hangouts for example.

One of the things that's likely to see a fair amount of attention is ART, or Android runtime. This was implemented in KitKat as an experiment, but now sits at the heart of how tasks are handled by Android. It's not something you'll be interacting with, it will just improve the performance of apps.

With Lollipop being so new, there's sure to be some apps that want to work with the previous Dalvik system rather than ART. Apps need to be updated to work with ART a process that's slowly taking place. When we initially looked at Android Lollipop, there were a number of apps, especially media apps that didn't run smoothly. A series of updates has removed many of the problems and apps continue to update all the time.

We're sure that this will only be an issue in the early days of Lollipop and by the time most people get it on their devices, we're sure that all apps will have been updated and run very smoothly.

There's also wider support for other media applications, with enhanced graphics support in OpenGL ES 3.1, there's enhanced audio capabilities, with support for USB speakers and mics, multi-channel audio mixing and more.

You also have native support for HEVC, meaning Android will be able to stream UHD 4K video, which is really aimed at Android TV. Like the audio features above, these things will be waiting for implementation rather than something you'll find any reference to when using your Android device.

Verdict

Android 5.0 Lollipop is a comprehensive step forward for Android, most noticeably through design. It's easy to say that there isn't a headline feature that makes Lollipop really appealing, but it's in the reworking of the core experience that the real strength lies.

In some areas Android has adopted popular features of other devices. There's still plenty of space to move things forward, but as it is, Android Lollipop has smoothed away some of the common pain points. For the Nexus devices this is great, but Lollipop's glory moment will be adding refinement to existing devices as updates roll out.

There are some aspects of Android Lollipop than we can't immediately access: Android TV and Android Auto are high on the agenda, as well as Android Wear enhancements, that make Lollipop a unified experience across multiple platforms.

The redesign, the addition of consistency in many areas, the enhancements of an already excellent notifications system, and convenience features like tap to wake and Smart Lock, make Android 5.0 an update you'll really want.

We hope that manufacturers don't ride roughshod over Lollipop, because it really is a very sweet take on Android. There's plenty more we want to see, but there's plenty to be excited about.

READ: Android 5.0 Lollipop: When is it coming to my phone?