I had 3G and then 2 years after that I got 4 on the launch day.
I'm still on 4 and will get the 6 probably. The only problem I have is that iOS 7 is a little bit laggy on the 4. To be honest, 4S,5 & 5S are not that massive upgrades for me except the camera. Yes, they are faster, lighter but thats about it. At the end of the day you want your PHONE to be fast enough to use it, take great pics etc. So I guess that the only thing for me to really need is the camera improvement as the other tiny things are progress guaranteed.
Skipping 4S&5 (I might get the 5S, will see) because I didn't have money for it then made me realise that I wanted to upgrade only because of my DESIRE and not NEED. I guess thats the same for most people and those that upgrade every year are crazy for me as I doubt they NEED a technology that they didn't know about.
So, with iOS 7 i actually hit the NEED button as the 4 doesn't cope so well anymore. Not to mention that my home button is dead and I have to use the accessibility feature to use it. Would be happy to have it fixed if the iOS 7 wasn't so laggy on the 4. Not gonna pay £120 for repair that will give me a phone that is still laggy but home button works. If they offered 4S when I pay then I'll be happy to pay and would even be happier to wait for the 6 or 6S

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