Tag Archives: cellphone

Using a foreign Sim in a Verizon Samsung Galaxy S3

One of the the things I was testing on this vacation was getting a foreign sim card to work on my Verizon Samsung Galaxy S3. LTE phones on Verizon all take sim cards now, and as of the 4.1 update for the S3 it’s supposedly unlocked as a world phone, at least the internet largely said so. As a dry run for the Hong Kong OpenStack summit I wanted to figure out if this was true or not by trying it in Canada.

Adventure #1: finding a Rogers

Rogers is one of the big telcos in Canada, and has a pay as you go plan with data. This seemed to be the best bet to figure this all out. Finding an actual Rogers though, turned out harder than expected. The address we had for Saint John didn’t have anything obvious, and unlike the states, there wasn’t a cell phone store in every little town. That meant that by the time we actually found a Rogers it was about 3 days into Canada, in Truro, in the mall.

The last time I did this was with a pre-smart phone in Germany, where their were telco stores in every transit hub, so I hadn’t actually expected the stores to be that sparse.

Adventure #2: the sim

Apparently the way I read everything online was only about half of what’s actually going on with Rogers. The prepaid plans existed, were a little differently structured than I expected.

The Rogers rep was very skeptical that a Verizon phone was going to take a Rogers sim, but they popped one out anyway, we rebooted the phone, and it didn’t lock out. It just showed a little funny icon in the notification area that there was a non-verizon sim in there.


This isn’t actually a problem, and you can long hold on it, realize the Setup Wizard is the app causing it, and kill it. Then you don’t need to look at it until a reboot, or about a week (it came back later for me which is how I got the screen shot).

Some time on the phone from the Rogers office and I had a Halifax number, a 500 MB data allowance, and some credit for overruns on phone and texting. It cost me about $60 CAD. The cell phone was on their network, Rogers sent me a few texts with my number, and off we went to Cape Breton.

Adventure #3: data

On the drive to Cape Breton, I realized there was no data service on the phone. That was kind of the point of all this, to have data. Of course without internet, it was hard to debug. Also, complicating things, was the fact that Cape Breton is a bit sparse on cell coverage. Which meant even if I could figure out a fix, it wasn’t really testable up there. A couple days in I started searching to figure out what the deal was, and eventually I got to the bottom of it.

While the Rogers sim did everything correct to get on the phone network, and the radios all worked for that, to get on the data network you need to define an APN. Pre Android 4.0 there were APIs for this. Post Android 4.0 there are not, however on the S3 you can manually create an APN. There is this good app in the market called Offline SIM APN Database which has all these settings, and lets you copy and paste them easily. A couple of minutes later you’ll have defined an APN. After that, reboot, it doesn’t really like to take APN definitions live.

So when we were leaving Cape Breton headed to Halifax, on the highway, back in civilization I finally had data on the phone. Just let it prefer Global mode and it was working. However, pretty quickly I noticed it was edge only.

Adventure #4: edge

Edge is basically the GSM version of 1xRTT (for people that live in CDMA land), and is slow. More searching basically led me to the fact that this was as good as it was getting on the S3. While the S3 was eventually opened up to be a global phone, it didn’t start that way, and it wasn’t really a design point for the Verizon version which added the 700 Mhz LTE radio. So the silicon doesn’t have 2100 Mhz, which is basically where most GSM telcos implement HSPA, their 3G. So we were on Edge for the whole trip where we had data.

Things that work fine on edge (even though they are slow): Google Maps, Foursquare, Facebook, Gmail

Things that get goofy on edge: Untappd, Accuweather (both seem way to data hunger, and not very happy if things reset connections).

I turned off sync while on the Rogers sim. Given the slowness of data this was very helpful for battery life, and for not having something else in the way when I wanted the data connection.

Conclusion: it works

At the end of the day, this all worked. Not having 3G was annoying, but fine. From what I can tell the S4 has all the radios to do 3G on GSM, as do some of the more recent Motorola phones on Verizon.

Alternatives: Verizon International Plans

When I finally figured out the APN issue, I also found my way to Verizon’s international plans. They aren’t actually all that bad, especially if you are trapped on edge, so data isn’t going to be used all that heavily. And even more so with Canada, which after you add the international plan, all the calls and texts are free.

I think that for future Canada trips (especially if we’re there for something shorter) we’ll just enable that on our phones instead of doing the sim route. However, on this trip the sim route was a learning experience as much as anything else.

Update (Jan 4 2014): Hong Kong

Because this post is getting a bunch of new finds on “the google”, I wanted to add a little more data. I went to Hong Kong a couple months after this. There I was able to get a 7 day unlimitted data sim for ~ $12 US. They set it up in the kiosk and I was online in about 5 minutes.

In Hong Kong I actually had 3G (HSPA+). So realize that 3G bands vary by country, and whether you’ll get 3G on your phone is actually hard to completely figure out in advance.

Also, I’m on Verizon stock firmware, and I’ve had friends have difficulty with this on Cyanogen mod on Verizon phones.