It changed because people wanted to make the phones more posh so people would want them more to buy.
You cannot change a phone's frequency.
It really depends on the cell phone company you have some don't let you change and some do. I would advise you to contact your local cell phone company.
Do edit, then retype the number.
yes. cell phone automatically change.
No. It might damage the phone, though.
Cell phone network extenders can be a wonderful way to improve your cell phone service. They are easy to install and are an affordable option if you do not wish to change your service provider.
screen change
Mobile Phones
no
Yes.
You can only do it by computer
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