I left iOS because I was bored with it in November and picked up a Nexus 6 with no plans to come back to iOS. I used Android exclusively for 3 months. I found that Android is very good, but still not as consistent or reliable as iOS. The Nexus 6 wouldn't hold a cell connection like my iPhone does, it had issues with certain Wi-Fi networks (drained tons of battery, heated up, lagged like crazy), would take upwards of 1 minute to connect to a known network, and the screen burned in after just two weeks of use.
I'm back on iOS now, and while I do like Android, it would be hard for me to go back since there are so many crippling issues it has. The iPhone cliché of "It Just Works" actually holds true in my experience and the fact that the cohesiveness and reliability of the Apple ecosystem is extremely good means that I will be using iOS for a long time to come. I would rather have a phone that is locked down and reliable over a phone that is fun to customize but isn't super reliable and has a few big crippling issues.