A few days ago, I posted reasons WHY someone would legally (in the USA) 'want' to swap IMEI numbers of a smart phone with a dumb phone. Now I'm posting HOW someone can just as legally solve this problem. In that 'why' thread there was much discussion (some of it rather unsubstantiated, seemingly from the UK crowd who had, apparently, little understanding of less-Draconian USA laws); but the net was that there are perfectly legitimate and wholly legal reasons (in the USA) for wanting to change the IMEI number of a smart phone to mimic that of your dumb phone. Nonetheless, I just want to report that, after all the research, I simply switched carriers from AT&T to T-Mobile and the desire to change the IMEI vaporized by doing so (i.e., this wholly different thread is the HOW I solved the problem - based in part on all the excellent advice you guys expertly provided). In summary: AT&T has an IMEI-penalty clause (in the USA) That clause penalizes any IMEI number "assumed" to be of a smart phone (arbitrarily, by AT&T) It matters not (to AT&T) whether that phone 'uses' data (or if the user even 'wants' a data plan!) In fact, you can install a 'data block' and AT&T will 'still' apply the monthly $25 IMEI penalty! That automatic $25/month AT&T IMEI penalty applies to any phone (no matter who owns or bought the phone or how it was purchased) as long as that phone is 'connected' to the AT&T network & if the IMEI number of that phone is on the arbitrary AT&T $25/month IMEI-penalty list One desired solution is to swap the IMEI with that of an (unused) dumb phone in your possession (in this case, a broken Motorola RAZR) By swapping IMEIs, you break no (US) laws; and you have absolutely no chance of causing network problems (the RAZR doesn't work anyway) Yet, simply by swapping IMEIs, you get the desired power of the phone applications, the Internet (via WiFi), the phone hardware such as the cameras, the phone touchscreen etc. of the smartphone ... all this sans the AT&T penalty data plan By way of contrasting solutions: T-Mobile does not have any IMEI-penalty clause (in the USA) You can put the T-Mobile SIM card into any phone (no matter what the IMEI number is - so there is no need to swap IMEI numbers) as long as T-Mobile did not subsidize the phone If the 'smarphone' is of an older iPhone, e.g., iPhone 3GS, you only need to jailbreak/unlock the iPhone (so that you can use T-Mobile SIM cards in that iPhone) Again, you cause no network instability & you break no (US) laws; and you get the power of the applications, the net (via WiFi), the cameras, the touchscreen etc. of the smartphone as there is no T-Mobile IMEI-penalty data plan In the end, I'm happy to report this solution, suggested by many of you, is cheap, fast, just as legal (in the USA), and, in the end, much easier than learning how to swap the IMEI number of your dumbphone with your smartphone! Comments/discussion always welcome, as we learn from intelligent dialog.