Samsung Galaxy Note 3 - Everyone is going to give you crap that its TO BIG.
Then they pick it up and play with it for 3 minutes and see what it can do. Next thing you know you have to remind them that this is YOUR phone and to give it back.
Have had mine for 6 weeks now. Don't know how I ever did without...
You need to narrow down based on what you expect to do with your device.If you expect to do some productive shit and need a wacom digitizer to draw and stuff , you are better off with the Note 3 . I personally haven't used the stylus after the first day because i did not find a use for it.
The HTC One is a beautiful phone and has a right balance of performance and aesthetics.
Lumia 1020 for the insane imaging capabilities.
Nexus 5 for the bang per buck and stock experience .
Note 3 again for brilliant battery life.
IF you buy anything else its probably not worth it.
The multi tasking makes every other phone on the market look like a toy. Plus I can charge my phone from zero to full at blazing speeds with usb 3 and then hold that charge for days with the massive battery.
I got a Nexus 5 yesterday. So far I really love the speed, it's the fastest phone I ever played with. If you use a lot of Google products, this is the best option IMO.