I don't believe the iPhone 3G can update past 4.2.1, but any newer iPhone can update the same way you normally update an iPhone through your iTunes authorized computer.
No the solstice ii is much newer than the iphone so it's hard to say whether it is better. I would upgrade to a newer iphone version because it is easy to use and works great and economical.
No, no newer version for Windows exists. They will be releasing a version for the iPhone and the iPod Touch however.
any
The iPhone 4 can currently run up to the latest version: iOS 7.1.
Iphone 4 cases are not compatible with 3g iphones because the newer iphone is not made like the 3g. They have different bodies are are much more angular that the 3g.
It is because it is the third version of the original device. iPhone is the first, iPhone 2 is the second, iPhone 4 is the fourth, and so on.
no, as long as your iphone is on the latest software version it is secure.
I doubt if you could ! Normally, you're only able to upgrade hardware and software to a newer version. That would be like swapping your current car for an older model.
Yes. Both the iPhone 4 and iPhone 4S work on Verizon's network. However, you will need to buy the version of the 4 or 4S that is compatible with Verizon.
no because the ipod touch 4 is a newer version
No. The iPhone 4 runs on iOS 4, the current version being 4.1.