iOS 5 and APN’s – the new wrinkle in SIM swapping

Tuesday, January 3, 2012

Carrier-unlocked iPhones have been progressively extended to more countries in recent months, including the United States.  For those who want to pay the added price, this brings the ability to roam internationally using local SIM cards (eliminating the perils of jailbreaking & unlocking via hacking) within reach of more people.  With the advent of iOS 5 however, Apple has taken a confusing turn by making us jump through more hoops to use our non-home SIM.

One important element of using a SIM card with a given network is the configuration of the APN or Access Point Name.  This is a simple domain name that helps your phone connect to the network associated with the SIM, helps it obtain an IP address, what security methods should be employed, etc.  It’s usually very simply formatted – the AT&T iPad plan APN, for instance, is simply “broadband”.  With a non-home network, it always needs to be configured manually, and in iOS 4 and prior, it was easily keyed from the Settings > General > Network.  With iOS 5 however, this option has completely disappeared.  I have tried roaming with my foreign SIM cards, and this setting is not downloaded automatically from the new network – you do have to set it manually.

So, here’s an easy solution (although not as easy as manually typing the APN).  Navigate to the site from your iPhone.  After selecting Continue, then Custom APN, you will be presented with a couple pop-up menus – one for the country, the other for the carrier/APN options.  Choose your Country (it should auto-fill the country you are currently in) and the Carrier name that matches the SIM you wish to use.  Incidentally, if you roam to the US using the AT&T iPad plan like me, the choice is AT&T (Broadband).  Hit Create Profile and it will bring up an Install Profile window, on which you will need to hit the Install button.  It will then verify your identity by asking you to type your iPhone unlock code, then it’s done.  Note that this will overwrite any existing APN settings in your iPhone, so you will want to do this only once you have arrived in your destination country.  The catch-22 is that you do need WiFi access to do this, unless you’re willing to spend $$ data-roaming on your home SIM card.  The settings files only seem to be about 14kb, so the cost is minimal, however any data-roaming defeats the whole purpose of my blog posts…

To remove the APN, once you return to your home region/SIM, just navigate to Settings > General > Profile (near bottom of screen) and hit the Remove button.  The additional APN script will then be removed and your standard settings reapplied.

While this process does introduce the catch-22 of having to have Internet access in your roaming region to install the APN required for your foreign SIM, it does eliminate the hassle of having to Google around forum sites for APN settings for a multitude of carriers.  Bear in mind as well that there may be multiple settings for one carrier (as there are for AT&T) and there may be some legacy data mixed in as well due to mergers and acquisitions (some of AT&T’s APNs have Cingular domain names within, as Cingular merged with AT&T some time ago) so there may be some trial and error involved in getting it right.

The unlockit site does also allow you to email any given APN script, rather than installing it directly, so another workaround would be to email yourself a variety of scripts, which you can then install by clicking on the email attachment within the Mail app.  Neither the email nor the attachment are named in relation to the country or carrier though (although the APN name does appear in the “Description” field when you click the settings file and link to the Install Profile window), so it may be confusing to keep track of a variety of these files.