The iOS device keyboard has some very useful features that make text entry easy and fast. For example, if you reach for a key and press the wrong one, keep your finger on the key, slide it to the correct key, and lift up. The correct character is entered. Here are some of the more common features of the keyboard and some neat shortcuts.
Type different versions of each letter and symbol by tapping and holding each character.
- To type an uppercase letter: Tap the shift key before typing the letter.
Many people have multiple e-mail accounts, and as already mentioned, they can access them all from their iOS device (see page 44). Your device uses the e-mail account you entered as the default account—whenever you send, reply to, or forward an e-mail, it is done from this account. If you have more than one e-mail account, you can change the default account by following these steps:
Starting with iOS 4, the Mail app started archiving instead of deleting Gmail messages. 
Your iOS device comes packed with accessibility features to help you use the device more effectively. They are particularly helpful to people with certain disabilities. To turn on or off the accessibility settings, go to Settings> General> Accessibility and select the feature you want to activate. They include the following:
When the Push option is turned on, and if your e-mail service provider supports Push, information updates are sent to your iOS device as your provider receives them. (MobileMe, Microsoft Exchange, Yahoo! Mail, and some others support Push.) However, leaving Push on all the time consumes battery power. Unless you have up-to-the-minute messaging needs, you should turn Push off and use the Fetch option, which checks for messages periodically. 
There may be situations where you'd like to stop receiving e-mail from one or more account. For example, you're on vacation and don't want to receive business-related messages. The following temporarily disables the account on your iOS device. 
Many people have multiple e-mail accounts—one for business use, another for personal use, a third for non-profit organizations you work with, etc. Occasionally, you might have to delete one of these. For example, if you change jobs, you'll want to delete your business account altogether. The following will delete the account on your iOS device. 
Your device lets you access all of your e-mail accounts, allowing you to send and receive messages wherever you are. There are several ways to add an e-mail account to your device. The easiest is to work with one of the five default e-mail services that your device recognizes automatically. 