I'm not sure of the context of your question, so I will assume you are asking if you can activate a cellular phone in the US, as opposed to activating a US Cellular phone (which is a wireless network in the US). Here are the different scenarios on activating a cellular phone in the US:
No reason why not - so long as the handset comes 'unlocked' from any network.
If Verizon does not have sim cards, then you can buy the phone from eBay and take it to get activated. Its simple. There may be a $15 or more activation fee, but it can be done. If Verizon does have sim cards then u can simply insert ur sim card in the new phone.
Since 7/15/03, US Cellular will NOT activate a phone unless it is US Cellular-sourced. That merely means that it was originally sold by US Cellular or an authorized agent. It does NOT mean you have to buy the phone from a US Cellular store. You CAN buy a phone from a friend, eBay, or wherever, but it MUST be US Cellular-branded. Also, phones can be direct-purchased from some manufacturer's, most notably Motorola. They will ask you who you're carrier is, and ship the phone US Cellular-branded. These phones can be activated.
It is possible to buy a cellular phone if you have a bad credit rating. If you purchase a pay as you go phone, there will be no checks on you what soever.
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Online you can buy a cellular phone amplifier at Amazon. Offline or online try Best Buy or another electronics retailer. Also try a mobile phone store for a specific carrier.
You can purchase a replacement cellular phone battery online from stores such as Best Buy. Alternatively, you can purchase these batteries from retailers such as Overstock.
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