As a web developer/online shop owner I'm about to buy my first iPhone when my current phone contract ends due to the high percentage of visitors viewing our sites on iPhones (10% last month). What I need to know from you experts is how the browsing of websites differs from iPhone model to model. This will help me work out a long-term buying strategy for iPhones. To put it another way, would an iPhone 5 bought now allow me to test for say the period of a 24 month contract? Or should I buy sim-free and sell/upgrade each time a new iPhone appears? Do I really need the latest edition for testing? For instance, browsing on my wife's iPad1 and my iPad4 is very similar (speed apart). I'm not bothered about having the latest phone personally although I do buy the latest iPads as I love them as a personal toy too. But I'll buy the latest iPhone and keep buying if it's the best way to go. Money's not really a problem on this but I'll save where I can.