On Fri, 18 Jan 2013, Chuck Cole wrote: > No, it's the spec that must be compatible, not just the brand. There are > other brands of CDMA spec phones. Phones belonging to one network in the US are not, are 100% NOT compatible with other providers. You CANNOT switch a phone from Sprint to Verizon for love nor money. Now perhaps there are phones that work on multiple systems, but this is not the norm. However, if I unlock a GSM phone, I can switch it between AT&T and T-Mobile quite easily, and unlocked GSM phones are readily available, because... > The fact that 5 of 7 providers don't use GSM is a significant comparison, > IMHO. But go look at the rest of the world. Virtually everyone uses GSM. The US and Japan are rare exceptions. This is why unlocked GSM phones are standard and readily available. I can take my phone and use it in practically any other county using a local SIM card. This is how cellphones work just about everywhere in the world - you buy a phone and you can take it with you between providers because they all use the same (global) standard. In the US, carriers tend to subsidise the phones, and therefor lock them to their own serivce. Even if the systems are compatible it's a pain to transfer over. Though GSM makes this significantly easier. --