Whether it's on tablets or smartphones, Apple and Google are definitely the 500lb gorillas of the industry at the moment, with Microsoft's Windows Phone 7 yet to gain a big foothold in phones and Windows 8 still a while out for tablets.
As if to drive that point home, we've got the release of iOS 5 and Android 4.0 Ice Cream Sandwich within a month of each other. Both of these adds a lot to its respective operating system, with iOS on the iPhone and iPad adding improved notifications, iMessage, Newsstand and much more.
You can check out our iOS 5 and Android ICS: What you need to know videos below:
Android 4.0 is a more visible change, bringing the futuristic look of Android 3.0 Honeycomb to phones, and adding a huge raft of features besides that, including removing the need for physical buttons.
With such big updates to both platforms, the only thing left to do is let them slug it out in a head-to-head battle…
iOS 5 vs Android 4.0: Interface
The big news here is all about the new-look Ice Cream Sandwich interfaces on phones and other small devices. Taking the seemingly Tron-inspired futuristic lines of the tablet-focussed Android 3.0 and toning them down a little, the new phone version of Android is all business. There's even a whole new font, created just for this new version of Android. You can't say Google hasn't put the effort in.
Apart from the cool blue lines, the obvious interface difference in Android 4.0 is the addition of the on-screen menu buttons (Back, Home and Recent Apps), which always stay on the bottom of the screen. Home screens now also have a Favorites tray, which stays at the bottom of every Home screen, much like iOS's Dock.
Android 4.0 even adds the option for resizable widgets on your Home screens, so you can choose exactly how much information you want to see at a glance. You can also now organise apps into folders by dragging one on top of the other, just like iOS's Folders feature.
Conversely, iOS 5 sees very few changes indeed to the interface. Many will say it didn't need changes; many will say it's time to mix it up. Either way, the only real change for iOS is the notifications in the Lock screen, and the addition of Notification Center, which pulls down from the top, much like Android's notifications on phones.
iOS 5 vs Android 4.0: Multitasking
Multitasking is another area where Android 4.0 brings features from the tablet-friendly Android 3.0 to smaller devices. Tapping the Running Apps button will bring up a a big, visual list of your recently used apps, complete with thumbnail showing how it was when you last used it. You can swipe across an app to get rid of it from the list, which will close many of its functions.
In many ways, iOS 5 appears very similar. Double-tapping the Home button brings up the Multitasking bar at the bottom of the screen, which shows icons for your most recently used apps. You can tap and hold on one bring up the option to close any of the apps.
The big difference with multitasking is under the hood. Android apps are capable of something closer to PC-like multitasking, where apps do whatever they want in the background, whereas iOS forces all apps that aren't currently being used into suspension unless they use one of the specific background functions that Apple allows.
Android's approach gives more freedom and flexibility to both users and developers, whereas Apple's approach is designed to prevent any performance issues with apps, and to preserve battery life.
iOS 5 vs Android 4.0: Customisation
Customisation has long been one of Android's strengths, and though the new interface is finally consistent across phones and tablets, we're sure many users will still want to tinker with custom launchers, live wallpapers and other tweaks. The resizable widgets are another big advantage here, letting you control how you see information with much more control than ever before.
We don't yet know what will happen with overlays, such as HTC Sense, on Android 4.0, but this is another area where Android can be made to stand out.
Customisation on iOS is rather less encouraged than it is on Android. You can change the background of your Home and Lock screens, but that's about it. Aside from deciding the best order for your apps, this isn't really the best platform for those who can't stand not being able to tweak every aspect of their phone.
The good news in iOS 5, at least, is that you can finally set custom alert tones for messages, emails and the like.
iOS 5 vs Android 4.0: Web browsing, messaging and social networking
In many web browsing benchmarks – which admittedly don't always accurately represent real-world use – the iPad 2 running under iOS 5 is one of the fastest mobile browsing machines on the planet, with the best Android 3.0 tablets very close to it.
In phones, the gap is currently slightly larger, with the iPhone 4S comfortably in front. However, Ice Cream Sandwich looks set the change that, reportedly bringing the faster browsing of its tablet heritage to phones, thanks to its ability to make full use of dual-core processors in lots of modern phones.
We don't yet know what the final speed shakedown will be, but you can be sure the two will be neck and neck.
Of course, Android will still have Adobe Flash, which iOS doesn't support. How much of an advantage you see this is as will depend on your own web usage.
Both operating systems have a wide range of email options, with lots of webmail account settings built-in, and corporate Exchange support on both platforms.
iOS 5 adds internet messaging using iMessage to iPhones and iPads, which enables you to send free messages, photos and video to other iOS users from any of your iOS 5 devices. Apple has also integrated Twitter into iOS, so you can tweet from many more places, and add Twitter names and photos to your Contacts app. FaceTime video calling to other iOS devices and to Macs is also built-in.
Android 4.0 adds more Google+ features, including messages and Google Hangouts, which offer similar function to Apple's iMessage and FaceTime features, provided your friends are on Google Plus.
iOS 5 vs Android 4.0: Apps
iOS 5 introduced some new apps on Apple's device, including the Reminders app for tasks and a new way of getting and organising your magazine apps in Newsstand.
On top of that, Apple's App Store is still the gold standard for the industry, even if the Android Market is now rivalling it for size. It's easy to find apps that are just for the iPad, just for the iPhone and iPod touch, or that work on both. With iCloud, you can buy on one device, or on your PC, and have the app download automatically everywhere else.
Android has offered cloud app purchases for some time, and has one particularly impressive new app of its own in Ice Cream Sandwich. Android Beam enables you to tap two NFC-equipped phones together and transfer just about anything between the two. It's incredibly slick.
Google has said that it doesn't want to differentiate between phone and tablet apps in the Android Market, because it thinks many will scale up from small to large screens just fine. While it's true that they will certainly be functional, we know from the most innovative iPad apps that you can do a lot differently in the extra space rather than just make the interface larger.
Both iOS and Android had camera upgrades in their latest versions, with iOS gaining photo editing abilities and a few other features, with a focus on speed on the iPhone 4S. Android has also added a photo editor, has also focussed on reducing the speed to take photos, but has also added real-time effects to the camera app, including the ability to replace the background during video capture.
iOS 5 vs Android 4.0: Specialities
Both iOS 5 and Android 4.0 have a few tricks up their sleeve to outfox the other. On the iPhone 4S, Apple has introduced the Siri virtual assistant, which can understand commands in natural language and with context.
See the section in our iPhone 4S review for more, but it's an astonishingly good feature, and it's still only in beta.
Android also has voice commands and dictation, but the commands are nowhere near as advanced as Siri.
Android's big advantage has always been the Google apps it usually comes with. Free sat nav in Google Navigation, a slick Gmail app, Google Goggles, Google Translate, and the list goes on.
iOS 5 vs Android 4.0: Updates
Android has always had a rocky time with updates, unless you're on a 'Pure Google' device, such as the Google Nexus S. There's often a delay between when Google releases new software, and when the phone carriers allow it go out to the devices.
Many phones don't get new upgrades at all, so while we hope that everyone with a newer Android phone will be able to update to Android 4.0, you'll have to check for your model with your carrier.
Apple bypasses this process completely. Thanks to having only a few devices to support, Apple can tell you exactly which phones are supported, and when you can download the update. iOS 5 is available on the iPhone 3GS, iPhone 4, iPhone 4S, iPad, iPad 2, and the two most recent models of iPod touch.
After iOS 5, all updates will pushed out over the air, so there won't be any need to plug in to get the latest version. Android updates have operated this way for some time.
iOS 5 vs Android 4.0: And the winner is…
Ah, if only it were as simple as picking a winner!
Apple has the more vibrant ecosystem of slick apps, but without the customisation options that many Android users will crave.
Android has the more flexible multitasking system, but with some performance issues that iOS devices just don't have.
Android has Flash, but loading Flash content often means that pages appear slower than on iOS.
It's impossible to say objectively which operating system wins this fight, but we know that many of you will have read through the pros and cons of both and come to your decision. Whichever way you think is best for you, there's no doubt that the phone and tablet markets are moving forward at an incredible rate now.
Liked this? Then check out 20 best mobile phones in the world today
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