@op
if you've ever owned an apple product (i have an ipod) then you would realize the deathgrip they have on usage. for instance i can copy songs to my ipod, but i cannot transfer them back onto the same pc even if they were bought using the itunes store. dumb right? welcome to apple.
i don't have any direct experience with the iphone (never had, never will) i can not give specifics but it appears that this is tied to itunes for syncing as well. as for the app store apple has a tight leash on devs...which has a good side but a bad side as well.
with android devices you can easily do things such as ...
changing themes, colors, launcherbars without rooting
free tethering to your laptop with root
play flash video
drag and drop music, video, etc to your phone
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as for windows phones go, i wouldnt suggest one as they dont have enough market share to be competitive.