BELGRADE, Serbia — The tens of thousands of migrants who have flooded into the Balkans in recent weeks need food, water and shelter, just like the millions displaced by war the world over. But there is also one other thing they swear they cannot live without: a smartphone charging station.

“Every time I go to a new country, I buy a SIM card and activate the Internet and download the map to locate myself,” Osama Aljasem, a 32-year-old music teacher from Deir al-Zour in Syria, explained as he sat on a broken park bench in Belgrade, staring at his smartphone and plotting his next move into northern Europe.
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Technology has transformed this 21st-century version of a refugee crisis, not least by making it easier for millions more people to move. It has intensified the pressures on routes that prove successful — like this one through the Balkans, where the United Nations said Tuesday that about 3,000 people a day continued to cross the border from Greece into Macedonia.

In this modern migration, smartphone maps, global positioning apps, social media and WhatsApp have become essential tools.

Migrants depend on them to post real-time updates about routes, arrests, border guard movements and transport, as well as places to stay and prices, all the while keeping in touch with family and friends.

Traffickers advertise their services on Facebook like any legitimate travel agency, with dynamic photographs of destination cities and generous offers.

On the Arabic-language Facebook group Trafficking to Europe, one trafficker offers a 50 percent discount for children under 5. The 1,700 euro price of the journey from Istanbul to Thessaloniki, Greece, about $1,900, includes travel by car to and from each side of the border with a two-hour walk across.
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“Right now the traffickers are losing business because people are going alone, thanks to Facebook,” said Mohamed Haj Ali, 38, who works with the Adventist Development and Relief Agency in Belgrade, Serbia’s capital — a major stopover for migrants.
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But as tens of thousands completed their journeys, they shared their experiences on social media — even the precise GPS coordinates of every stop along their routes, recorded automatically by some smartphones.

Buy the biggest capacity microsd card you can find and load it up with as much data as you can. This lets you have some necessary information available for when you don't have internet.

The effected area after a disaster is generally pretty small. Even with nuclaire disaster, the exclusion zone is only 20km (Fukushima) or 30km (Chernobyl). The 2004 Tsunami only reached 2km inland. So cell service might not be that far away.

War, flooding, hurricans, typoons will have bigger effected areas, but you can see them coming. Having rapid information (be it early warning, traffic information or just satnav) might be the key to get out quicker, and make it far easier to figure things out outside the effected area. A smartphone is a pretty good tool for that.

The trend in phones seems to be to do away with the microsd card slot. For various reasons, I find this a bad thing.

But I also found a work around: some smartphones will host a USB "thumb" drive via their own usb port. You need to use a small adapter cable called an "OTG" cable.

Not all phones will do this; it seems that most of the later versions of Android will do it. In some cases, the phone will require the installation of an app, but my Samsung Galaxy S3 handles it just fine with its standard software, Android 4.3

Having this available both gives you backup and also lets you conserve memory on your phone if it is limited by not having an sd card slot.