Brick_Pig said:
Here's a list of new features and a short description of them:
http://gizmodo.com/ios-8-new-features-for-your-iphone-and-ipad-updating-1584820649
The article more or less assumes you're moving from iOS 7 to iOS 8. If, as you say, you are moving from iOS 5 or 6, there were obviously things in between that you've missed. Although there are certainly some cool new things, in reality the basic functions of the phone stay pretty similar across the upgrades. Best thing to do is just jump in a mess around with it, as you mention.
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