From The Sip Trunking Experts

TMCNet:  Which mobile phone is best for roaming?

[January 31, 2013]

Which mobile phone is best for roaming?

(Guardian Web Via Acquire Media NewsEdge) I want to travel to other countries, buying sim cards for each one. Which phone should I get Kindratyshyn Different countries use different mobile phone systems, and almost always use more than one waveband. However, GSM (Global System for Mobile Communications, originally Groupe Spécial Mobile) is by far the most common, and has about 85% of the global market.

GSM is a second generation (2G) system, because the first generation of mobile phones used analogue systems.

GSM was adopted by the European Conference of Postal and Telecommunications Administrations (CEPT) and became the standard for Europe. Qualcomm's CDMA – used by Verizon and Sprint – was already running in the USA, but carriers such as AT&T and T-Mobile have now moved to GSM. You can probably get a GSM signal in most if not all US cities.

Japan also used its own system, developed by NTT, the national phone company. The NTT DoCoMo standard is not used anywhere else. Today, however, you can use third-generation (3G) GSM in Japan and South Korea.

GSM networks run at different wireless frequencies, and almost all countries have two. This led to the popularity of dual-band phones. In Europe, the two bands are 900 and 1800MHz, whereas the USA (and a couple of other countries) use 850 and 1900. Covering all four frequencies requires a quad-band phone.

3G is more correctly called UMTS (Universal Mobile Telecommunications System) and it is supposed to use the 2100 waveband. Not every carrier complies. The American government was already using this frequency, so some carriers resorted to alternatives. For example, Cingular's 3G network uses 850 and 1900, and T-Mobile has used 1900 and 2100. It means some 3G phones will not work with some American 3G networks, which a problem for Apple iPhones.

At the moment, many carriers are marketing fourth generation systems, which may use either WiMax or, more commonly, a version of LTE (Long Term Evolution). However, 4G is more of a marketing term than a technical term, and it looks like being an even bigger mess than 3G. It's OK as a local system, if you need the extra speed and are willing to pay the price, but I wouldn't recommend it for roaming.

However, I do recommend getting a phone that includes Wi-Fi, so you can use Skype and other internet services from free hot-spots. This is even cheaper than using a local sim.

To sum up, you should buy a quad-band GSM phone that supports 3G UMTS 2100 (Band 1) as a minimum. If you compare specifications, you will find some 3G phones also offer UMTS on other bands including what the Americans call Band II (1900), Band IV (1700 or AWS), and Band V (850). Yes, this is crazy.

Before you buy a phone for roaming, check the specification very carefully. What looks like the same model phone may be designed for use in a particular country or even by a particular carrier. In fact, it's safer not to buy a carrier-branded phone at all, as these are usually locked to the carrier that has subsidised the selling price. A locked phone won't necessarily work with a different sim card.

Sim cards All GSM mobiles must have a sim card, and they now come in three different sizes. These are the standard mini-sim (25 x 15mm), the micro-sim (15 x 12mm), and the nano-sim (12.3 x 8.8mm) used in the Apple iPhone 5. (Mini-sims are called sims for short, because nobody remembers the original credit card-sized version.) When buying a phone for roaming, it's much better to go for the standard mini-sim. You should definitely not buy one that uses a nano-sim at the moment. Standard mini-sim cards are instantly available in phone shops and at many airports. You have less chance of getting a micro-sim, and almost no chance of getting a nano-sim.

You can use a standard mini-sim in a micro-sim phone by cutting it down, preferably using a punch, but this requires extra effort and is not guaranteed to work. While most carriers will swap a standard sim for a micro-sim, they usually do it by post. This is not much use if you are in a foreign country and need to make calls in a hurry.

You can often use a micro-sim card in a phone that takes standard mini-sim cards by slotting it into a small plastic carrier. However, this does not work with phones that have push-in sim slots, such as the Nokia N8 and Samsung Galaxy Note. See The Curse of Micro SIM Adapters at All About Symbian for photos and gory details.

In some phones, the sim is stowed under the battery, so it is inconvenient to change. It usually means you have to re-enter the date and time as well. Slots are handier, and some Nokia phones have an Easy Swap system that allows you to swap sims without turning off the phone.

Dual sims Some phones can also take two sims at the same time, so you can have one for work and one for personal use. This would be particularly handy for roaming. There are not many mainstream examples, but the Samsung Galaxy S Duos S7562 is a top-brand Android 4 smartphone that should do the job for a reasonable price. Otherwise, China's Huawei is a major mobile phone supplier with a large selection of dual-sim mobiles.

You could also look at the Free Your Mobile website, which sells more than a dozen models on its All dual sim mobile phones page.

Free Your Mobile has a £199.99 Android touch-screen phone that it describes as by far the best selling and performing Android dual sim phone currently on the market, without formally giving it a name. However, it looks like the Chinavasion CVFD-M306 (£107.95), which is also widely available as the HDMI Droid.

I've not actually seen or tried one, but it's a quad-band 3G phone. You have to take the back off the HDMI Droid to get to the two sims, which sit side by side. At least they are not underneath the battery.

There are loads of similar 4.3in and 3.5in screen dual-sim phones available from and the dropshippers who serve an army of eBay sellers and small traders, as well as some more adventurous consumers.

Dropshippers of tech products may be based in Hong Kong, and sell cheap products sourced from mainland China. Quality is not guaranteed, you may not get much if any after-sales service, and the ultimate price can be inflated by customs charges, so "buyer beware". You can pick up bargains; you can also get scammed. If you use Western Union to send money to Shenzhen, I don't see how you could get it back.

One final thought. A friend who is a permanent traveller (has a job on a large yacht) says she tries to buy data-only sims for roaming, and then makes phone calls using Skype. There's no point in having dozens of voice numbers that rarely work, is there (c) 2013 Guardian Newspapers Limited.

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