There were problems with iOS 6.1 and Microsoft Exchange that appeared to fixed in iOS 6.1.2 the latest iOS update. Previously there was an update for iPhone 4S-only (6.1) due to a battery drain problem with some networks, especially Vodaphone.
The "Exchange calendar bug that could result in increased network activity and reduced battery life" is fixed with the update. Last week Apple acknowledge the problem and offered a temporary fix.
The Apple support documents reported that the update is for iPhone 3GS, 4, 4S or 5 as well as iPad 2 and later. The iPod touch 4th generation and later can also be updated.
The software does not fix the security hole that allows other to access phone contacts and other information from the lock screen by canceling emergency dialing and tapping the power button
One January 28, Apple released iOS 6.1 for iPhone 3GS and later(4, 4S 5) , iPad mini, iPad 2, iPad 3rd generation and and iPad 4, as well as iPod Touch 4th generation and after. The iOS 6.1 update added LTE in some markets, fixed bugs, added Siri ticket buying as well as other features.
To update over the air:
- Make sure your iPhone is connected to a power source. To avoid potential data costs connect your device to a Wi-Fi network.
- Go to Settings > General > Software Update. iOS will automatically check for available updates.
- If an update is available* you can tap Download to download the update.
- After the download has completed tap Install to update your iOS.
- If an update is available* you can tap Download to download the update.
- After the download has completed tap Install to update your iOS.