11/11/2013 03:11 pm ET Updated Jan 23, 2014

KnowRoaming Review

Do you travel overseas? If so, you know the dreadful dilemma you probably face: stay in touch using your existing cell phone and come back home to a mega-sized phone bill; or go to the effort to get a local SIM card for every country you're traveling to, then email your new numbers to all your friends and business associates. It's a big problem for anyone who travels beyond our shores.
But there's finally a solution, at least for ATT and T-Mobile customers and Verizon customers with newer phones. Those phones are GSM and thus use SIM cards. Sprint and older Verizon phones don't. (And T-Mobile itself now offers its own solution - more about that later.)
The solution comes to us from KnowRoaming. It's a sticker that you apply to your existing SIM card (using an applicator that the company provides). Inside the sticker are some clever electronics that intercept your phone's communication with the SIM card. When you're in the U.S., the card has no effect on your phone (save for one minor annoyance, about which more later). But when you're roaming internationally, the sticker reduces your voice and data charges by up to 85% in more than 220 countries, and it keeps per-message text message charges at a manageable level as well.
The sticker performs this magic by automatically connecting your phone mobile to local wireless carriers in each country you visit. You pay for the calls by preloading the sticker with US dollars, so you don't get bills from the local cell carriers. Your account balance - the preloaded money - never expires. The company does not require any bundles, contracts or minimum commitments. Whatever you don't use on one trip will be waiting for you on your next.
And wait - there's more. The sticker also allows you to keep your existing number even while roaming. That is, people can call your US number and they'll reach you. Also, when you call people, your existing number is displayed.
There's yet another feature. While you're in say, France, what if French people want to call you? Do they have to dial your American number, thus incurring international charges? No, because the sticker also gives you a local French number. Your phone will actually have multiple numbers - your existing number, and the number in any country you travel to.
Another feature: the sticker reduces the price of calls from one foreign country to another. So, for example, if you're from the U.S., are visiting France, and need to call the UK, the cost of your call is less than it would be without the sticker.
All of this requires a lot of processing behind the scenes on KnowRoaming servers. Don't ask me how it works, because I don't really know. There are patents pending.
All of this is only activated when the phone leaves its home country. The magic turns off automatically when you return home. There are supporting apps for iOS and Android that enable account management and provide local rate information. (You don't make or receive your calls using the app; you make them using your phone's normal "phone" app - i.e., the same way you make or receive calls now.) You can also find rates on the KnowRoaming website (scroll all the way down on the home page).
The sticker costs only $35.
Let's look at some sample rates, continuing to use France as an example. According to the website, your rate for calls back home is $0.31. Incoming calls to you are a mere $0.07. Texts - incoming or outgoing - are $0.19. Data is $0.13 per MB.
There's even a way to reduce the $0.31 cost of calls back home: you can use a callback feature. The way this works is that you place the call and, instead of going through, the phone hangs up. A moment later, your phone will ring. When you answer, the phone you're calling will ring also. When the other person answers, you'll be paying just $0.11 per minute.
Now let's suppose you want to call the UK from France. Perhaps you're checking up on your hotel reservations for your next stop. Here, the price for making calls is higher: call through (the normal way of making calls) is $0.57 per minute, while callback is $0.37 per minute. Incoming calls and texts are the same rates as calls and texts from the U.S. ($0.07 and $0.19).
Any caveats? A few small ones. For one thing your phone has to be unlocked. T-Mobile will send you an unlock code at no charge after you've owned the phone for about 30 days. According to T-Mobile, it can take from 1 to 14 days, so plan in advance. I don't know ATT's and Verizon's policies re unlock.
Also, while your in the U.S., there is one difference that you'll see on your phone: in the notification area on the phone (pull down the window shade from the top of the screen), there is a notification that says "Home." This is to tell you that you're in your home country. That seems unnecessary, since you already knew that the U.S. is your home territory. This notification wastes a bit of space in the notifications area, but unfortunately there's no way to suppress it. (I aksed the company to make this possible but they declined.) In fairness, this is just a slight annoyance.
Speaking of T-Mobile, that company now offers global roaming in 115 countries on its Simple Choice plan (their regular, postpaid plan) that may make the KnowRoaming sticker less desirable for T-Mobile customers. The T-Mobile website explains that calls are $0.20 per minute (a customer service rep told me this applies to both incoming and outgoing calls), while texts and data are free, i.e., unlimited. If you're on the $50 or $60 plan, data speeds get throttled to a paltry 128 KB/sec. if you use over 500 MB or 2.5 GB, respectively, just as is the case when you are in the U.S. (In contrast, KnowRoaming operates at 3G/4G speeds regardless of how much data you use.)  T-Mobile also offers an unlimited data plan at $70 per month.
T-Mobile doesn't charge extra for global roaming, but you may have to call the company and have the feature activated on your plan. In any case, for T-Mobile customers, the KnowRoaming sticker may be less desirable than before. Still, you can always get the sticker and use it in certain countries if it's cheaper, while deactivating it in other countries.
So far as I know, ATT does not offer global roaming, so customers of that company will want to consider the sticker.
The sticker is available for preorder now through November 14 at KnowRoaming, and is scheduled to ship in February. It already exists in beta form - I have one on my cellphone, but have not yet traveled overseas to see how it works. Check out my reviews of other gadgets, Bluetooth devices and more.
Disclosure: KnowRoaming provided product for this review.