Camera-wise, definitely THE best (not taking the 808 into account), albeit, if you need video, the Note 3 can be a better choice.
Otherwise, the 1020 has a pretty dated hardware and, just like iOS, a closed-garden OS.
All in all, personally, I wouldn't buy it. Waiting for the next Nokia imaging flagship with up-to-date hardware.
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Again:
- if you need Android, then, the Note 3 / LG G2 is definitely a better choice than the N5, as long as you don't need Qi (again, which is possible with the Note3), SlimPort or frequent and prompt OS upgrades.
- iOS phones are entirely different animals. I personally don't prefer iOS to Android / Symbian but I do need to admit that there are some games (e.g., Spectromancer) that don;t exist on Android. Also, for the tech-unsavvy folks (Apple's main target people), iOS devices can be the easiest to learn / operate as they're made to be overly simple. All in all, if you absolutely need iOS, then, you'll need to accept it simply doesn't have the goodies current Android / WP handsets have. Nevertheless, as long as iOS-only devices are concerned, the 5s is a high-end phone.
1020 with quad core and 1080p?