Need mobile data in the U.S.? Here's how

This Huawei E5372 portable hotspot is compatible with T-Mobile's network in the U.S. and helps you share the data from one SIM.
(Credit: Michael Tan/CNET)

So, you're heading to the U.S. with your smartphone and dreading the lack of mobile data you're so accustomed to having in your home country. You're also unsure whether your hotel has free Wi-Fi. Now, you're wondering whether you can tether your iPad to your mobile phone for data with U.S. SIM cards.

You figure you'll need to get mobile data because you intend to use Google Navigation while on the road, or risk end up getting lost. Furthermore, you're dreading the multiple calls you'd have to make to your spouse just asking "Where are you, dear? Are you ready to go? I'm at the entrance of the mall." and paying expensive roaming charges every minute. Lastly, you're worried that when someone from the U.S. needs to reach you, they won't bother to call your Singapore phone number.

If any of the above scenarios sounds familiar and if you're wondering whether you should get a U.S. SIM card, here are the results of my research.

First, consider how much data you need. Don't underestimate the amount of data required, especially if you're going to use Google Maps and Navigation much more than you would in your home country. I consume about 2-3GBs a month in Singapore, and I estimate that I'll use that amount in two weeks in the U.S..

Secondly, you'll need to do cost comparisons. Singtel's Unlimited Global Roaming plan, charges S$30 (US$24) a day. This means you would have to pay a whopping S$420 (US$336) just for the data, for one phone. That's not ok in my book.

Thirdly, plan the strategy. The ideal way would be to get 2 SIM cards, one for you and the other for your spouse. Or maybe three SIMs, with the third SIM for your tablets and other devices.

I did the maths, and found that the best value for money SIM card was the T-Mobile SIM Starter Kit which retails for US$39.88 and comes with a SIM card and US$30 of value. This gives you unlimited data for an entire month, with the first 5GB at LTE speeds if your device supports the LTE band. I bought three of these.

Do note that the US$30 T-Mobile starter kit is not available from the stores, it's an online-only deal. In fact, it's such a secret plan that most T-Mobile employees don't even know it exists! You can buy it online exclusively from Walmart.com.

This card comes as microSIM. I bought a S$10 SIM cutter with me before I went to the U.S., just in case. You might need it to cut the micro-SIM to a smaller nano-SIM. You might also want to have on hand microSIM converters it to work on phones that use the larger SIM cards. You can get them from any neighbourhood mobile stores in Singapore.

If you know that your hotel in the U.S. accepts shipments, then you deliver the SIM card to you, otherwise, Walmart can ship to one of its stores or a Fedex office where you can pick up your SIM.

When I arrived in the U.S., I simply picked up my SIM cards from the nearest Fedex office. Unfortunately, they didn't work -- but it was probably just bad luck. I went to a nearby T-Mobile store and they replaced the SIMs for me.

Lastly, these SIMs need to be activated online but I didn't bother with that. You can head to the nearest T-Mobile shop and get them to activate it for you.

I put the SIMs into my HTC One as well as my wife's Samsung Galaxy S, while the final SIM went into a Huawei portable hotspot dongle to share the data with my tablets.

As for voice calls, I used two cheap feature phones and put our Singaporean SIMs inside -- just in case someone from home needs to reach us.

Interestingly, the hotspot needs to be configured for T-Mobile once you put the SIM card in. My hotspot device is compatible with LTE, and you just need to load up T-Mobile's APN settings for the Internet. It's available here. It might sound complicated, but all I had to do was to change the APN name to fast.t-mobile.com and a link was established.

T-Mobile's coverage in the city is excellent -- I had full bars everywhere I went in Los Angeles and San Francisco. Even smaller cities like Bakersfield gave me excellent reception. Unfortunately, I only got HSDPA+ connections (despite selecting the LTE option in my dongle), but this might change in the near future as T-Mobile re-deploys some of their frequency bands to LTE. Nevertheless, H+ was sufficient for all my needs in city areas. Viber, Skype and Whatsapp worked perfectly both for text and messages, and Voice over IP worked fine.

However, coverage was not so great in rural areas. Yosemite only gave me EDGE connectivity, and in Tahoe I had 3G but not great reception. Google Maps and Navigation worked fine even with an EDGE network, but it will take a longer time to start or do a redirection.

I found it difficult to get the T-Mobile SIM to share bandwidth with my phone's Wi-Fi tethering function. When I tried it, all the tethered devices displayed a registration screen to register the device as an authorised device.

Another point for travellers to note that is even if you change the SIM card in your smartphone, Whatsapp, WeChat, Line, and Viber will still work via the phone number you first registered with. The only thing that was changed in your handset is the telco's voice and SMS services.

Having the T-Mobile SIM enabled me and my wife to call each other cheaply and easily as a local call - the T-Mobile plan comes with 100 minutes of free talk time.

Lastly, the T-Mobile staff may tell you that the US$30 plan can't be used for mobile Wi-Fi hotspots -- but it sure worked for me on my Wi-Fi hotspot. Still, things might change in the future, so this is not a guarantee that using a hotspot dongle will work for you.