I have used both iPhone [Original, 3G, 3GS, 4] and Android in the past and at present I am using Android on HTC Desire HD. There’s no doubt that iOS and iPhone are awesome, but still [now] I am addicted to Android and here’s why:
1. I believe Android’s keyboard is one thing which I like most. Its replaceable. I believe it has more options. At the bottom of the keyboard you have 4 arrow keys, which help you a lot. If while writing, at later stage you come to know that you have misspelled any word, you can use those arrow keys to reach that word quickly. On iPhone you have to do [struggle] this with your fingers, which sometimes [read mostly] is time consuming.

Second thing about Android keyboard is writing in all caps. On Android you have to press the shift key a little bit longer and it just works. On iPhone you have to Enable Caps Lock in Settings ->General-> Keyboard and then double tapping on shift key enables caps lock for writing in all caps. Believe me many people still ask me how to write all caps on iPhone.
2. Another thing I like about Android is that I can directly store a contact on my SIM as Android gives me many options while storing a contact.
3. Another thing I like on Android is the capability to store messages as drafts. As I write a message and in the middle of writing a message I press the home button or back button, the message is saved as draft and I can view all my drafts separately. On iPhone, if I press home button while writing a message and then go to messages again, it opens that same message, no Drafts feature at all. Unless otherwise you complete or cancel that message, you cannot write a new one.
4. Next thing is Bluetooth. Transferring songs to my Android phone via Bluetooth is damn easy. I can transfer songs in bulk also, by just connecting the phone with wire to my PC and putting all songs in one folder and later on I can arrange those in playlists also. No need to download a fresh version of iTunes every two weeks or so. People in countries like India are reluctant to understand the working of iTunes.
5. I have the ability to put only the apps I require (GMail, Messages, Music, clock etc.) on home screen. Folders are again disliked by many.
There are many other Android features that the iPhone doesn’t have like Choice for Keyboards, Widgets, Removable battery & storage [not in all android phones], FM Radio, Flash etc. as noted down by lifehacker.
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