Apple no doubt . Always best and for ever. For development objective c is necessary ,that is easy and meaningful. More over world class user interface make it so popular. drawback:high price.
No one can object that Apple products are really great; their products have the best mobile features anyone can dream of hence the demand but for people who wanted options when it comes to their gadgets then Adroid OS is indisputably great too. Besides if it all comes down to performance Android has proven its worth too and with their big price difference who won’t love to get hold of one right?
iOS 5 is all set new and best featured at present and iphone5 is expected to get released in the month of September. The below link takes you to the information on all the features: http://www.bookscopy.com/ios-5-complete-guide-and-list-of-all-the-200-features/
According to my point of view both are best on the other hand I use iPhone which has become my favorite.
A young friend of mine summed it up rather well.. IOS is like when your mother cleans your room. Everything is neat and organized and easy to find. Android is like when you clean your own room. It may look like a mess to others but its your room done your way.
Apple apps are much more advanced and cooler than android. I had an android phone and an iphone so i can compare them. There are millions of apps that are useful, fun, and cool in apple.