I am having trouble with the Bluetooth on my iPhone 4 and iPad 2. When turning he bluetooth on any of the devices they do not see each other. I know the bluetooth works on the devices as other devices that i have can see both iPhone and iPad. Anybody help please??
Unfortunately, the Bluetooth function of the iDevices is not so they can see each other. It is only so you may use Bluetooth accessories such as headphones or keyboards. Apple didn't make it so that your phone can see the iPad and vice versa.
It is possible to pair iPhone 4 and the iPad 2 with bluetooth. It's use is limited, mostly as a way to tether; a legacy of the iPhone 3 and/or 3G, which can not create a wi-fi hotspot (if I remember correctly).
Most apps that will use bluetooth to communicate between the two device will establish their own connection, not depend on the one you create in settings. Even the Keynote remote app creates it's own bluetooth connection.
I can't offer a lot of guidance on how to create the connection. I mostly stumbled into it on mine. Just open up the bluetooth settings on both devices. Turn bluetooth on/off on each until one of them sees the other, then try to pair. If it does not work in one direction, try the other. Eventually some combination worked for me.
The iPhone is probably the only phone you can pair (without jailbreaking).