As much as some of the locked down aspects in iOS irritate me (especially when its known what is possible with iOS per all of the capabilities once jailbroken), some things keep tugging at me and pulling me back toward iOS. Probably the key reason is ability to AirDrop/iMessage/FaceTime with one of the kids who only has an iPad/iPod. Those who have pre-teens can probably relate to this.
The list below is what I'm contemplating, and if I do move back to iOS/OS X; want to make it for the long run as transitioning can be time consuming and not error free (migrating data from OS X to Windows apps, or the reverse). There are many equally compelling, and unique things I like about Android and the Google ecosystem that I think work just as well or better than iOS and the Apple ecosystem; and that's part of what is creating the challenge.
1. No bloatware
2. Guaranteed updates
3. Timely updates
4. Less security risks (Nexus devices not included)
5. Communications (iOS natively, of course, supports iMessage, Messages and SMS relay in OS X, FaceTime, and SMS; plus Hangouts, Skype...)
6. Battery life (excellent on the 6+, 6S+)
7. Good integration with OS X, iCloud and it's and overall ecosystem (if one has an OS X system)
8. Good app selection (same is true with Android in my experience, so consider those equal)
9. TouchID (same is true with Note 5 in my experience)
10. Apple Pay (all of our major bank cards are supported, not the case with Android or Samsung Pay)
11. Cloud storage (iOS natively supports iCloud of course, Google Drive, Dropbox, OneDrive...and so does Android minus iCloud)
12. Productivity (Microsoft Office Suite, Google Office Suite)
13. Support (we are fortunate to have several Apple Stores in our metro area, and in my experience Apple online/phone Support has been quite good when needed)
14. Family Sharing (works well for approving/managing kid's iOS app purchases)
15. Entertainment (Apple TV is good, and the Remote App works well. I do like Google Play + Chromecast quite a bit though and use it frequently with Note 5)
16. Apple Watch (while not perfect, in my experience its the best so far for a smartwatch + general fitness tracker; and I've tried Tizen and and Android Wear based watches)
17. iTunes compatibility with the older radio in my truck (yes I could buy a new radio with Bluetooth and Android+iOS capability, but don't want to invest the hundreds of dollars on a 10+ year old vehicle when USB support works with the current radio, and I can charge the iPhone at the same time).