Both OS's are good in their own right, I always remain objective when comparing the two.
One thing I wish android has that iPhone does so well is compatibility... iPhones paired with other apple devices just work instantly and without the need of setting anything up, its almost magic (cliché sounding I'm aware). Also apps.. they run better on iOS, are released first on iOS, and get updates quicker.
I guess also a messaging app like iMessage. Hangouts kinda does the job but not really at the same time.
Edit: I asked the iPhone sub the same type of question, let's see what they say lol.
Thank you for sharing this feedback with us all!
Being able to imessage across devices is probably my biggest need. I sometimes will put my phone in another room to avoid distractions but I can still access it via the my laptop. Also for the life of God, I just want blue instead of green bubbles across the networks lol