-First of all, the iPhone handles WiFi horribly. If I get out of range of my router, it takes close to a minute for the iPhone to realize it needs to switch to 3g for data. It's terribly annoying when I walk my dog and want to listen to music using Audio Galaxy.
-Also, Bluetooth is not only annoying to turn on and off, but like WiFi, it is horribly unintelligent. I had a bluetooth headset on and went into a store to get something and left my phone in the car. I was out of range of my bluetooth. When I got back in the car, my bluetooth reconnected and Siri worked through it fine, but when my wife called me, the phone decided I didn't want to use Bluetooth anymore and redirected the sound to the headset and not my ear peice.
-Email is not nearly as good. If my phone is sitting idle next to me, it stops getting emails until I start using my phone again. This is horrible when I'm deep in project and don't realize that I've gone 2 hours since checking my email
-Reception SUCKS! I get complaints almost every day that people I'm on the phone with can't hear me. I've never had this problem with any BB I've owned which were used in the same locations as I'm having problems with my iPhone.
-Battery is decent at best. I can get through the day without charging, but it's cutting it VERY close, usually going to bed with about 8% battery left. My 9930 wasn't any better, but every other BB I owned was MUCH better.
-I miss my physical buttons. I like having a menu button always located in the same location as well as the back button. With the iPhone, each app has these buttons located differently which is more annoying than people would think.
-The lock screen is annoying. I like how with my BB I can press the lock/unlock button on the top of the phone to unlock my phone and it's ready to use. The iPhone I have to press the unlock button (or home button) and then slide the unlock bar to start using my phone. After years of not having to do that, it slows me down noticably.
-iOS5 doesn't recieve Twitter notifications for new tweets. I use Twitter a lot and have to manually check for new tweets instead of getting a notification every 30 minutes. It's a known bug on iOS 5 that is annoying.
I know some of that stuff seems like I'm nitpicking, but combined, they are a big deal. The iPhone 4s is incredibly smooth and fast, but it doesn't do the imporatant things well.
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