I still prefer my nexus 4 over iPhone 6 or 6 plus(because I can't live with IOS), and I also prefer LG G3 or HTC one M8 over iPhone(just my options, there are iPhone fans too).
in my options current Android phones are already better.
Why i prefer android phones over iPhone:
1) Cheaper
2) Better screen (one of the main reasons i choose android phones)
3) Smaller yet bigger screen
4) Android (my main reason to choose android)
5) They look better and HTC one m8 feels so awesome in hand! (personal option)
6) Better sound
7) Features
Note 4 advantages over iPhone:
1) Better screen - but has purple smudging on some places!
2) Bigger screen
3) Cheaper (not much but still cheaper)
4) Accurate S-Pen
5) Some of the Samsung bloats are useful
6) It has Android
7) It has an Micro SD Card slot
8) OTG ( I don't think iPhone has OTG, does it?)
9) I'm not sure but some stuff are faster (but saw a video on YouTube)
10) heart rate (don't think its useful anyway)
11) uses Micro USB
12) turbo charger - its amazing ! 1% per min, 100% in around 1 hours
13) can have wireless charging
14) General-purpose NFC
15) According to GSMArena: 10:44h of web browsing vs 9:05h and 17:25h of video vs 11:15h and 28:34h of 3G talking vs 23:49h my battery life is good ! with HSPA+,HSPA and locations on etc i get like 6-7 onscreen time when browsing etc games(4 hours for games as i calculated) i never ran out of battery when i was outside!
16) Camera samples look so much better to me
17) I love the build quality, metal frame mixed with soft fake-leather is perfect ! i prefer it over HTC one m8(Metal stuff like metal pens make my hands feel bad!), iphone feels cheap in my hands (i barely saw it, it had screen protector so it might be the reason)
Note 4 disadvantages:
2) Bad fingerprint sensor -- Edit: its not actually bad, but not as easy as iphone, it barely gives me any errors
iPhone 6 plus advantages:
1) Better fingerprint scanner
2) Better benchmark results
3) lighting cable is easy to plug
iPhone 6 plus disadvantages:
1) Overall feeling of the phone was terrible in my hand
2) It's big (but has small screen)
3) I hate the home button (feels terrible to use)
4) can't Bluetooth to others(only iPhone to iPhone).
5) Doesn't have MicroUSB.
6) IOS animations are cool but are really long for me. i get bored waiting for them to finish!
7) Expensive accessories etc
BTW: I don't think anything really exiting is coming. so it won't change much, Maybe a new SoC and battery life!
Edit: I got an note 4 as a gift and it changed my mind and edited few stuff i love it so much