Take a look at Macworld's: iPhone vs Android: Why the Apple iPhone beats Google Android.
Smartphone makers take it in turns to trump each other for storage, processor speed and camera megapixels, but it’s the largely software - the mobile OS - that makes the biggest difference to your everyday use.
We're not talking about just the interface. It's the features the software offers, plus the depth and breadth of apps available for the mobile OS which make a difference.
It's all very well being able to download the big hitters such as Twitter, Facebook, Angry Birds and BBC iPlayer, but what about the smaller apps such as online banking, other catch-up TV services and more? If your chosen mobile OS doesn't have these in the app store, your smartphone will be more limited than you might want.
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Popularity is not necessarily the best guide either. The Apple iPhone quickly stole market share from BlackBerry and Nokia, but now plays second fiddle to Google Android in terms of the number of devices sold.
A resurgent BlackBerry - thanks to the recent launch of the BlackBerry 10 OS along with a more consumer-friendly BlackBerry Z10 handset - could win back former fans.
Microsoft’s Windows Phone 8 isn’t out of the running either. It's certainly one of the 'big four' mobile OSes and has its own strengths and weaknesses.
It may be that you already have an iPhone or Android smartphone and would prefer to stick to what you know, but with every high-profile handset launch and mobile OS update, the competition gets stiffer. The Android or iOS device of three years ago is barely recognisable from today's models.
How to choose the right smartphone OS for you
Price vs. OS version
The cost of your contract partly reflects the hardware capabilities and amount of storage on your phone, but you should really judge the value by what the mobile OS offers.
Any current iPhone can be updated to iOS 6 (the latest version of Apple’s mobile operating system) for free, but whether or not you can update an Android phone to the latest 4.1 Jelly Bean version depends on the operator and the device itself.
Samsung’s Galaxy S3 is upgradable, but the cheaper Galaxy Y supports only Gingerbread (Android 2.3). Some budget phones such as the Sony Xperia tipo ships with Android 4.0 Ice Cream Sandwich, but is unlikely to ever get an upgrade to Jelly Bean.
To get the latest BlackBerry OS, you need to either the BlackBerry Z10 or the business-focused Q10 handset.
Windows Phone 7 smartphones can’t be upgraded to the latest Windows Phone 8 OS, but some can be updated to Windows Phone 7.8 which adds a similar home screen. Again, availability of the update depends on the manufacturer and operator.
Let's look at the mobile OSes in turn.
Apple iOS 6
The latest version of Apple's mobile OS which runs on the iPhone, iPad and iPod touch offers the broadest choice of apps of all smartphones and comes with plenty of Apple’s own apps.
The likable Safari web browser supports multiple web pages, but the lack of support for Flash means some websites don't work. Synchronised bookmarks (via iCloud) and the ability to save pages for offline viewing (Reading List) are handy. In-private browsing is supported.
Typing is fairly swift once you master overriding Apple’s autocomplete suggestions. Good note-taking, reminders and calendar apps are provided.
Email support is equally solid. You can easily add multiple email accounts from Outlook to iCloud Mail, Yahoo, Google and Exchange, then designate contacts as VIPs. You can view inboxes separately or show all messages in a single inbox view. Mail is searchable by name or subject via a field at the top of the screen.
Voice search via the Siri digital assistant is largely a gimmick and requires a Wi-Fi connection to use. The ability to view documents sent as attachments is welcome, but they can be saved locally only if you have certain apps installed which support those file types.
iOS 6 has a handy Notification Centre and you'll see notifications appear on the Lock Screen so you don't need to unlock your phone. You can also disable all notifications between preset hours (the Do Not Disturb feature) so you can avoid distractions.
A central Settings app is used to manage almost every element of iOS, with on/off toggling for Bluetooth, roaming, in-app purchasing and third-party app integration. Some parental controls are provided and it's easy to synch and backup using iCloud or iTunes.
You need an Apple ID to buy apps and to manage most elements of your iOS life. Purchases can be viewed or installed on any other iOS device you own (up to five computers can also be registered to your iTunes account at once).
Music, games, TV shows, film rentals and other iTunes purchases can all be deleted to free up space and subsequently downloaded for future viewing. You get 5GB of iCloud storage, but photos, videos and purchases don't count against this. Of course, you can pay for more or use Dropbox, Box.com or other cloud providers.
Apple replaced Google Maps with its own Maps app in iOS 6, but you can still get Google’s superior maps app which also includes Street View. On the iPhone 4S and 5, you get turn-by-turn driving directions and the pretty-but-pointless 3D view in major cities.
Integration with audio hardware is impressive via both Bluetooth and Apple AirPlay wireless streaming (Apple's TV is great for wireless streaming too).
Aside from the sheer number of apps in the App Store, one of the big advantages of iOS is that Apple curates all apps, so rogue installations (and malware) are less likely than with Android.
See also: iOS 6 review
Next page: Google Android
While iOS is managed with a firm hand (some might say iron fist) by Apple, Google Android is more of an open-source renegade. This hasn’t always played out well.
Alongside the ability to gamble and view porn (a no-no for Apple users) are security issues. As long as you install apps only from the Google Play Store and use recommended app security software you should be fine. Since NFC (near field communications) and mobile payments are supported, ensure you don’t make payments or log on to financial websites unless security is active.
Google Ice Cream Sandwich (the version before the current Jelly Bean) covers all the basics, with fancier media management options (Samsung. HTC and Sony) and prettier weather and contact features (HTC in particular) being added on some handsets by manufacturers.
More confusingly, mobile operators such as Vodafone and Orange pimp their handsets with preinstalled entertainment extras and their own separate lists of recommended apps. In the past, these extras have interfered when upgrading to new Android versions.
Google is doing plenty right, though. Android advocates are a fast-growing army. One clear advantage is the well-developed Google Maps app. Strong mapping, 3D and satellite views are accompanied by built-in voice-control and turn-by-turn navigation. Android also offers built-in voice search, NFC support, screen mirroring and contactless content sharing. You can ‘throw’ photos and music to devices across the room and queue up actions in a form of home automation (that's all dependent on the particular handset, as not all support NFC).
Android’s app selection exceeds 600,000, with anything you’ve bought or downloaded for free to one Android device automatically available on any other you buy - everything is linked to your Google account.
This contrasts with Apple’s separate apps list for iPhone and iPad - not all apps are 'universal'. There’s a limited magazine selection – don’t worry, PC Advisor is one of them – but the books section is as strong as Apple’s iBookstore. The Movies list numbers dozens rather than iTunes’ hundreds. Netflix and LoveFilm complement both. iOS is stronger for kids’ games and educational content and for creative apps.
Some users will be put off by Google’s apparent ability to know everything about their web use, email accounts and personal details. Being logged in to the default Google Chrome web browser won’t help. A Google account is used to manage app and other purchases.
Google Now (which is now available for iOS devices, albeit in a slightly more limited form) serves up useful information based on your past behaviour, but also on location and time of the day. Travel information, currency rates when overseas and other pertinent information is served up as a flash card when Google reckons you’ll find it most helpful. This does nothing to dispel the idea that Google knows your ever move and thought, but much to prove its slavish devotion to you, its customer (and ad-supporting cash cow).
Next page: Microsoft Windows Phone 8
Windows Phone 8
Windows Phone 8 takes full advantage of nothing but large-screen handsets being designed to run it. Luxuriously large tiles offer access to People, Calls, Music & Videos, Xbox games, apps, Calendar, Camera and Photo gallery. Swipe down to reveal Office 365, SkyDrive and Local Scout – a location-based food, drink, business and entertainment finder. Entries in our neighbourhood were very limited. Helpfully, if you need to drive to a location, your Windows Phone 8 will dig out an appropriate app from its Marketplace app store to assist or launch one you’ve installed.
A Microsoft ID is required (Hotmail, Live, Xbox or Outlook.com email addresses all work, but you can use any email address) to manage your account. You can then access Xbox Music Pass unlimited streaming (30-day trial then £8.99 per month or £90 per year). Film rentals are also managed through the Xbox portal. As with Apple’s iTunes, you can preview 30 seconds of any track. Text messages, photos and emails can be automatically synched – photos are posted to your SkyDrive. You get 7GB of free storage.
Windows Phone 8’s app repository mimics the slickness of the Google Play Store and offers 120,000 to choose from. If Find My Phone is switched on you can browse the Marketplace on your laptop and have apps install automatically over Wi-Fi – a slick option that allows you to browse app options in comfort before buying. NFC and contactless photo and message sharing are supported too, so you can beam shots to friends on ICS and Jelly Bean Android phones.
One of the highlights - if you happen to have young children - is Kid's Corner. This is a walled-off area of the OS where you can give your kids access to games, apps and other things without the worry they'll email your boss or delete your photos.
Although there are some great smartphones available running Windows Phone 8, it's the lack of choice in the app store that holds it back. BBC iPlayer has only just arrived, and there are still many, many useful apps which are missing: available only to Android or iOS users.
Next page: BlackBerry Z10
BlackBerry lost out when other smartphones (mainly iPhone and Android) used apps to tempt business users and touchscreens began to prevail over keyboard-driven interfaces.
BlackBerry 10 is the former business and teen-messaging brand’s comeback. It’s a decent revamp, with an infinitely swipable screen that eventually takes you through all the content on your phone.
It makes the few home screens on Android and iPhone handsets seem a bit passé. Navigation is still a little strange though. You swipe upwards from the very bottom of the Z10 to unlock the phone, and can then peek at incoming messages and friends’ status updates via a vertical split screen. A 3D effect sees you zooming in and out of panes. BlackBerry’s new mantra is that everything is seamlessly connected and you don’t need to dive in and out of separate apps to see what’s happening.
Messaging support is unsurpassed, with amazingly fast text entry possible. Word suggestions pop up as you type but without distracting you. Contacts, BBM and text messaging apps, plus a Remember app to prompt you about appointments are included.
Web browsing is very slick and, as with previous BB operating systems, media management is very good. You can rename as well as enhance photos, then search for anything within your media library. Disappointingly, you can only use BBC iPlayer in its browser incarnation and downloads are not supported, as they are for iOS and Android. However, the BlackBerry 10 version launched before the Windows Phone 8 one, suggesting at least one big app player’s confidence in its future.
More than 70,000 apps launched with BlackBerry 10 OS in January, many of them high-profile such as Kindle ebook reader, Skype and WhatsApp for free messaging and media download tools to come. Business apps are well represented, while social media must-haves Facebook, Twitter and the more corporate LinkedIn are all preinstalled. Skype is promised soon.
Installing apps is straightforward, though app reviews on BlackBerry World are understandably scant. Music, Games and Books are presented as sections of a single app and content hub.
Video editing via the excellent Story Maker joins the standard photo, music and video libraries in BlackBerry 10. Docs To Go offers native document editing. Store and sync them via Dropbox or Box online archives. You can even Print To Go.
NFC smart tags and voice controls ensure BlackBerry 10 covers most bases, but there’s no stand-out feature to put this slick system ahead of its rivals. However, for many people, it's the dearth of apps which make the Z10 or Q10 less appealing than a new iPhone or Android handset.
Next page: verdict
What's the best mobile OS: Verdict
Apple is still way ahead of the game for sheer app numbers, but the volume can be overwhelming at times. Even with its mostly-useful updates and tweaks, iOS is starting to look tired and Apple is widely expected to announce a big revamp for iOS 7 at the WWDC in June.
Android suffers from quality issues, especially where apps are concerned. Unlike Apple's tightly controlled world, Android devices have all sorts of screen sizes, resolutions and performance.
BlackBerry 10 and Windows Phone 8 are playing catch-up with app functionality and integration (mainly with choice, it has to be said) but both have slick performance and the advantage of having been designed for dual-core handsets, so performance is universally good.
Microsoft would have you believe that Windows Phone 8 is the best choice if you already use a Windows PC, have an Xbox or even a Windows 8 tablet. However, although there are some benefits to a unified interface, there's nothing really compelling.
Android has support from top brands such as Sony and Samsung that also offer entertainment portals across consumer hardware, but is still fighting off some poor app quality issues. It's flexible, though, and there's a big choice of hardware no matter what your budget.
Vodafone loaned us a BlackBerry Z10 and HTX 8X for this article.