Andriod or Windows phone all the Way, Apple is far to restrictive (depending on your intentions, Wink Wink)
HTC One or One M8 or Samsung S5 on Andriod or Latest Lumia i would strongly recommend, as for heuhens remarks about repairability most modern smart phones are wank..... this is apples saving grace, i have repaired numerous Iphones, Ipads and Ipod touches and apart from being a bit fiddly are easy to repair and the parts tend to be relatively cheap of eBay... screen etc.
my own Ipod Touch has had 7 screens, yes I'm clumsy but it still works fine and has cost me no more that a tenner to fix each time........
back to your original question IPhone 6 is probably best as having held a template of a 6+ you need a huge pocket............
Ships in the yard...
River and Hunt class Mine sweepers
AVRO Shackleton all marks WIP
C17 Globemaster III (UK Version) (US Version no rush up for grabs) (mostly done)
C5 Galaxy somewhere between 75 and 85% (WIP)
E3 Sentry RAF, French, USAF Saudi inc KE3 and RE3 and NATO (WIP)
KC135, RC135, EC135 and other various modifications.......(WIP)
AU.. Commonwealth of New Cromer.... 1.1% see link below
http://www.shipbucket.com/forums/viewto ... =14&t=5079