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The 411: Unlocked phones on a prepaid network

Every two weeks, Senior Associate Editor Nicole Lee answers your questions about cell phones, smartphones, and all things mobile.

Welcome to the 411, my column answering all your questions about cell phones and cell phone accessories. I receive plenty of questions about these subjects via e-mail, so I figured many of you might have similar queries, too. At times, I might solicit answers from readers if I'm stumped. Send your questions and comments to me at If you prefer to remain anonymous, let me know in the e-mail.

Can you use an unlocked Samsung Galaxy S II on a prepaid GSM network?
Can you use an unlocked Samsung Galaxy S II on a prepaid GSM network? Josh Miller/CNET

Question: I am a tech enthusiast, and have carrier-hopped around trying the latest and greatest cell phones. I can break down the technical side as well as anyone, but the one thing I can never get through is carrier policy. My question for you is twofold. For me specifically, if I purchased an unlocked Galaxy S II, would it be possible to use it with a prepaid service, such as GoPhone? In general, what is the guidance that dictates which phones will work on prepaid plans? Do prepaid carriers blacklist certain phones (iPhone, Nexus One) to ensure that even non contract users are stuck paying for services they don't need in their bundled smartphone packages? -- Jacob, via e-mail

The short answer is yes, you will be able to use a prepaid GSM service with a GSM unlocked phone like the Samsung Galaxy S II. Simply pop in the activated prepaid SIM card and you should be able to make and receive calls. Bear in mind that you might be subject to data charges, which are rather pricey for AT&T's GoPhone network--ranging from $5 for 10MB to $25 for 500MB. However, we can't guarantee that there won't be any hiccups along the way: we've heard occasional reports of the data not working, or calls not getting through. Certainly make sure the phone you're using is a quad-band GSM phone at least.

As for whether there's a blacklist of certain phones, I do know that AT&T generally doesn't like it if you use an iPhone with the GoPhone network, but there is a way to do so if you get an unlocked iPhone and a separate GoPhone SIM card. It's sort of a workaround, but it's possible. If any of our readers have experience with using an unlocked phone with a prepaid SIM, let us know.

Hi Nicole, I am in need of your advice. I am a licensed PA realtor and I need a recommendation for a smartphone. I need Internet access with fast speeds. A good camera with a flash, email access (MS outlook) and great battery life. Can you please help me out? With so many phones on the market I don't know what to buy. I had a Samsung Vibrant, but no flash and it locked up way too much. I also had an iPhone 3GS but I felt it was a downgrade from the Vibrant and it had no voice activated navigation. Please help me out? Thanks -- gmoton, via e-mail

There are a lot of choices that meet your specifications. You should start by narrowing down a choice of carrier or OS if possible. But if you're open to anything, you could take a look at our Best Camera phones list, as the camera seems to be one of your top features. The iPhone 4 tends to be the best choice for a camera phone. If you want a phone that also has fast 4G speeds, you could opt for the HTC Inspire 4G for AT&T, the Samsung Galaxy S 4G for T-Mobile, the Samsung Nexus S 4G for Sprint, and the HTC ThunderBolt for Verizon Wireless. There are plenty of other choices out there of course, and more arriving all the time, so I would urge you to narrow down your preferences a touch more. If any of our readers have other suggestions, let us know as well.

After years of corporate BlackBerry use, I'm finally switched over to iPhone 4 as my company's IT dept supports it. Love the phone/interface as I expected I would, but I'm struggling with the small font size of the news feed section of the Facebook app. Even with "cheater" glasses on, I find it to be much too small to read comfortably but can't seem to find a way to increase the font size as with those controlled within the settings/accessibility options in the phone itself. Any ideas as to if and how the font size can be increased within the FB app? Twitter is small as well, but looks to be maybe a point larger than the FB news feed. I've searched on an answer, but can't seem to find one, so maybe one doesn't exist. Thanks! -- Scott, via e-mail

With the iPhone, you can adjust the font size for Calendar, Contacts, Mail, Messages, and Notes within the Accessibility section, but not for third-party apps unless the developer builds that option into the app. For example, there is a Font Size section in the Settings for the Twitter app, but the Facebook app does not have any Font settings. One workaround you can try is to simply access your Facebook page on Safari, and then use the pinch-to-zoom function to zoom in on the page. It's a rather clunky solution, but unless Facebook decides to have the Font Size setting in the app, there aren't many other options.