Whether taking and sending photos or looking up directions on the go, smartphones have become an essential accessory for many globetrotters. In fact, in 2011 one out of three handsets sold worldwide were smartphones, reports the US market research firm IDC.

Yet despite the recent hype around the iPhone 5 (which goes on sale around the globe on Friday), only approximately one in five smartphones sold worldwide this year will likely be an iPhone. In the global race of smartphone sales, Samsung (maker of the Galaxy) is in a two-horse race with Apple (maker of the iPhone), followed by the third most popular manufacturer, Nokia (maker of the Lumia), according to data from US market research firm Strategy Analytics.

So given that other mobile phone developers are successfully challenging Apple, the previous industry leader, which device is the best all-in-one tool for travellers?

To give a taste of your options, we’ve compared the flagship smartphones from the world’s best-selling manufacturers: the Apple iPhone 5, the Samsung Galaxy S III and the Nokia Lumia 920.

All three have typical smartphone amenities that travellers adore, such as primary cameras that take eight megapixel images (which compares favourably with the two-megapixel-image standard of regular mobile phones) and they all shoot high-definition video.

iPhone 5
Arriving to 350 Apple stores worldwide 21 September

Cleverest travel tool: The newest iPhone  uses Apple’s new iOS 6 operating system, which has a travel-friendly built-in app called Passbook. (Users of 3GS, 4 and 4S and the second- and third-generation iPads can upgrade to iOS 6 for free.)

Passbook lets you store and collect many tickets electronically, including boarding passes for participating airlines such as United, American, Delta and Lufthansa, plus train reservations on Amtrak, and hotel reservations for participating chains, such as W Hotels. Rather than searching for an e-mail message with a bar code on it (whether printed on paper or saved electronically) or a particular screen on an airline or travel management app, all of your relevant reservation information is stored in one place, accessible with one click from the iPhone’s home screen.

Biggest drawback: Non-Apple devices (including those listed below) have, as a general rule, removable SIM cards -- memory chips that store data including contacts. The new iPhone 5 has a nano-SIM, whose non-customary format makes it difficult to convert the iPhone for international use by buying a local, regular-sized SIM card, which in turn grants access to cheaper data and calls on foreign networks. Eventually, international vendors will likely start selling new nano-SIMs, but in the meantime, travellers are out of luck.

Worth noting: Any latest-generation Apple device, such as iPhones from 3GS onward, allows free video chats between Apple devices using the free FaceTime app. Depending on your carrier and your location, the iPhone 5 can support FaceTime chats over a cellular connection, but there is never a charge for data transmitted by wi-fi. (Skype mobile apps offer a comparable free service for iPhone, Android and Windows Phone devices via wi-fi, too, and over some cellular networks.)

Samsung Galaxy S III
Released worldwide May 2012  

Cleverest travel tool: Samsung has made the most of the Android operating system’s slight edge over other smartphones in delivering accurate, prompt spoken GPS navigation. The Samsung Galaxy S III lets users summon driving or walking directions via its voice-recognition software, S-Voice, which then works with Google Maps. Apple has similar voice-activated driving or walking directions on the iPhone 5, pairing its voice-activation technology Siri with its new maps app, created using data from navigation specialist TomTom, but Samsung has been offering voice-driven turn-by-turn directions for a much longer time and has a head start in fine-tuning its service. More crucially, Samsung and other Android devices are powered by Google Maps, the Internet’s most used mapping database and heavily supplemented by user-generated feedback, making it more comprehensive than TomTom’s maps.

Biggest drawback: If you’re someone who assumes that bigger is better, then you’ll like that the Samsung Galaxy S III has the largest screen of nearly all smartphones on the market, at 4.8in tall, compared with 4.5in for the Lumia 920 and 4in for the iPhone 5. (Samsung’s niche Galaxy Note currently has the biggest display of any smartphone at 5.3in tall, though the holder of the title for largest smartphone screen switches perpetually among the manufacturers LG, HTC and Samsung.) Yet some users find that the Galaxy S III, whose overall dimensions are 5.3in by 2.7in, is too large to easily use with one hand.  

Worth noting: In a rare bonus, Galaxy S III supports micro SD cards -- memory chips that are compatible with many cameras and laptops – which makes it easy to transfer files and photos back and forth between the phone and other devices that also support micro SD cards.

Nokia Lumia 920
Arriving worldwide 21 October 

Cleverest travel tool: Nokia’s Lumia 920 is the first major smartphone to make augmented reality a standard feature. Just click on the phone’s City Lens tool, look at the street you’re standing on by viewing it through the camera’s viewfinder, and you will see overlaid information such as arrows pointing you in the direction you need to go based on your search, or information about nearby cafes, restaurants and other attractions worth visiting.

Biggest drawback: The Lumia runs on the Windows Phone 8 operating system, which isn’t yet served by many app developers, meaning some of the more popular travel apps found on Apple and Android operating systems won’t run on the device.

Worth noting: The Lumia 920 is the first major smartphone to use wireless charging, meaning that instead of juicing up the battery via a plug in the wall, you can instead lay the Lumia 920 on top of a pad, such as the Fatboy Pillow, which uses magnetic induction to charge the device. The advantage is that the Lumia 920 works with more than one brand of wireless pad, and you’re not beholden to buying the company’s proprietary charging cord – even if future Nokia models have differently shaped ports. This flexibility contrasts with the iPhone 5, where Apple has shrunk the charge port from the size used for previous iPhones, which means even current iPhone users need to purchase new accesories if they upgrade to the latest generation device.

Carriers matter, too
Remember, the device you have isn’t everything. The main worry global travellers face is avoiding extortionate roaming charges for using a foreign telecom network.

The best advice is to contact your carrier to find out if your device can be used abroad at an affordable rate, and what its rules for international travel might be. Our guide on using your cell phone abroad has other cost-savings tips.

Sean O’Neill is the travel tech columnist for BBC Travel.