If nothing else, for development anyway, it only costs a one time fee of i think $30 to host things on the google play store, but its $100 every year to renew your apple development license.
no brainer there.
as for other stuff, i would the same as others that there are way more free apps, and its a lot more freedom to do what you want.
the main difference being is that an iphone is "locked down" so much it hurts, and as a techie, i want the freedom to change things if i dont like it.
that said, i do think apple makes a good product that works well enough that things don't need to be changed ever, and thats saying something.