To connect to the Apple Wireless Keyboard:
(Note: This works for the iPad and the iPhone 4 and iPhone 3GS running iOS4.)
Turn your Apple Wireless Keyboard on. It comes with the batteries already inside, so you can use it right out of the box.
Tap on Settings on your iPhone.
Tap on General.
Tap on Bluetooth.
Turn Bluetooth on, if it’s not on already. Keyboard Not Paired should appear. Tap on it. A dialogue box will appear telling you to enter a passkey on the keyboard.
Enter the passkey and press enter.
Wait until the keyboard is connected.
Your iPhone is now paired with your Apple Wireless Keyboard.
To reconnect your iPhone with your Apple Wireless Keyboard:
Turn Bluetooth on, if it isn’t on already, by tapping on Settings > General > Bluetooth and then turning Bluetooth on.
Turn on your Apple Wireless Keyboard. In a few seconds, it will connect.
Connecting a Non-Apple Bluetooth Keyboard:
If you want to pair your iPhone or iPad with another brand of Bluetooth keyboard, the procedure is similar. But there are a few differences.
When you pair with the keyboard the first time, you will probably need to find and press a tiny connection button. Check the instructions that came with your keyboard to find this button. It is usually inside the battery box.
Once you have pressed the connection button, you’ll see the passkey dialogue box, as above. Enter the numbers on the keyboard and press enter.
Reconnecting an iPhone with a Non-Apple Bluetooth Keyboard:
When you want to reconnect to your non-Apple Bluetooth keyboard, you will probably find that turning the keyboard on isn’t enough to make it reconnect.
Check the instructions that came with your keyboard. You may need to press a combination of keys to force it to reconnect. For instance, to make the MP-0118+ keyboard reconnect, you have to press the CMD and Find keys together.
You may also need to force your keyboard to reconnect by going into Settings > General > Bluetooth and tapping on the keyboard’s name in the list after you’ve pressed the key combination.
If your keyboard has not connected in a few seconds, press the combination of keys and the keyboard listing again.
If the keyboard refuses to connect, change the batteries and try again.