First, I have owned a several Android phones. I'll give you that I haven't owned single one released in the past two years; but I got sufficiently burned with my Nexus S and Galaxy Nexus, and the awful upgrades to ICS and JB, that I admittedly still hold a grudge.
Second, my law school graduating class was about 300 people. Of those with smartphones, which was about 90% or higher, it was a pretty even split between iOS and Android. I didn't do an exact count, but it's pretty easy to tell from afar. When sitting in the largest lecture room, you can see who has their phones plugged in to the socket available at every seat. When a phone was plugged in to charge, it was an Android phone. In the largest lecture room, about 100, I would see maybe one or two iPhones charging, and I would see several dozen androids charging. From that, of my 300-person class, I estimate that about 100 of them are carrying an android charger in their bags at all times. Of note, I never say any of the people with dumbphones charging.
This isn't scientific, and it is anecdotal. However, I think it's a pretty good back-of-a-napkin estimation. I don't know what specific models these people had, but it's clear to me.
If I were to pick a random android phone from a pile of android phones, that phone would have worse battery life than if I were to pick a random iOS phone from a pile of iPhones.