If you don't plan to get a new phone within 2 years of buying this one I would go with any iPhone. There support is pretty good. They just stopped supporting the iPad 2 and iPhone 4 last year (2016). Android phones usually don't get that long of support.
if you want speed I would also recommend the iPhone SE or iPhone 6s as they still have a really fast processor (A9).
If you want features ( Curved display and ECT.) and a bigger battery I would recommend any Android phone in that case. iPhones are great but the battery's on them are pretty bad.