A: The extra $100 for theIf price is your main issue, then I think you'll get a great iPhone experience with the $99 iPhone 3G. But, if money is third our fourth on your criteria list, I'd say that you'll enjoy the added features from the iPhone 3GS.
Q: Though I love my iPhone, I'm not a fan of its call quality or
A: Android phones like the MyTouch 3G and the i7500 successfully rival the iPhone on many fronts. They won't offer exactly the same experience, but you'll find touch displays, full HTML browsers, multimedia features, and access to third-party applications. The hardware, of course, will be different, but that might be a good thing, depending on your personal preferences.
I also ran your question by our smartphone guru Bonnie Cha. Like me, she hasn't had any hands-on time with the Samsung i7500, but she says that if you're looking purely at specs, the i7500 offers more higher-end features--such as a 5-megapixel camera, more memory, and a 3.5 millimeter headphone jack--than the MyTouch 3G. Yet, unlike the MyTouch 3G, we don't know if the i7500 will ever come to T-Mobile, so you run the risk of waiting for a phone that may never appear. We haven't heard anything about an availability date.
If you really want to switch carriers, I suggest that you seriously consider an Android phone. It will offer much of the same benefits as the iPhone, but you'll get to return to T-Mobile. When the MyTouch is available, be sure to evaluate it for your needs. And in the meantime, our
Q: I'll be traveling to Japan and Hong Kong for business, so I'll need a phone that will operate in both countries. While I know that my T-Mobile quad-band GSM phone works in Hong Kong, I'm not sure if it will work in Japan.
A: As you note, your T-Mobile phone will work in Hong Kong without any issues. Hopefully, you can get it unlocked, which will enable you to use a local prepaid SIM card. Check out CNET's quick guide to world phones for more information on using your T-Mobile phone abroad.
Japan, however, is another story. Your T-Mobile GSM phone will not be compatible with the country's domestic cellular networks, so you'll need a handset that support's the country's 3G (WCDMA) technology. Such phones are not widely available in the United States, though you can rent one from T-Mobile. Alternatively, there are several U.S. companies that can make arrangements (try a Google search--I can't recommend any in particular) or you can rent a phone after you arrive in Japan.