I have a 1020, 5S and Sony Xperia Z1 all in use now.
1020 takes the best photos on a phone. No point even trying to argue that point. Nokia provide a lot of add on in terms of apps and services. But windows phone does have the weakest app store selection. However, I was surprised that I only was missing one app that I needed. There are workarounds and solutions.
5S vs Z1 http://gavinsgadgets.wordpress.com/...xperia-z1-share-you-view-on-the-better-phone/ have a look at my camera shootout and you decide. From my eyes, the 5S took more natural shots in terms of colours. But otherwise it is your call as to which you prefer.
I am also impressed with 1020 having optical stabilizer, and the Smart and Pro photo apps with a lot of innovative features.
Here's my view on it however... I wish Nokia would just make a camera with a bit of zoom lens and has no phone built in. Not having any zoom lens is pretty lame if photography is important to you.
Also DPReview noted:
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The bad news is that when it comes to camera operation, the 1020 is sluggish compared to the competition. Whether using Nokia Pro Cam or the standard Windows Phone camera app, shot-to-shot time hovers around a glacial four seconds, long enough to leave many users frustrated.
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http://m.connect.dpreview.com/post/5234892048/nokia-lumia-1020-camera-review?page=6
To me photography is about capturing moments. A 4-second recovery time between shots is unacceptable to me. iPhone 5S may not have 41mp or ISO controls but it does have super quick performance with zero lag and produces excellent shots. I'll not concede the Lumia camera is "hands down better" when it takes four seconds between shots.
1020 has lots of cool software features for photo manipulation and special effects, and I thought these seemed like they would be a lot of fun to play with, but would not be enough to make me deal with the lag. I'm less into special effects myself, though, than some folks. I could see those Smart app features appealing to certain folks, maybe people who don't care as much about recovery time.
I'd recommend getting a wifi-enabled digital camera or an EyeFi card and using those instead of your camera phone, except when you're in a pinch. To me there is no replacement for a real camera. I also like not using up my phone's batteries taking pictures, because I take a lot of pictures.
The Canon S110 HS or SX510 HS both work with Canon's nice WiFi app and provide fully manual controls over all functions. The SX510 can do up to 240FPS video and has a 30X stabilized optical zoom that works during video recording for $250. Personally I'd go with a NEX-5T from Sony or a Canon Rebel, or pick up a used Nikon D300s for $500-600 and pop an EyeFi card in it. Shrugs.