How can I connect Bluetooth headset?

How can I connect my iPad to my iPhone via bluetooth and use it as a speaker and microphone for Phone.app like an bluetooth headset?

• I know you can do this on the Mac with the Dialogue app.

• Answer:

  Play audio to a Bluetooth accessory If you want to play audio to a Bluetooth accessory, you'll need to select the accessory. You can do this by using the AirPlay option in Control Center. While on a call you can tap audio and select the device you want to use. Check your Bluetooth connection To see if a Bluetooth accessory is connected to your device, look for the Bluetooth icon in the status bar of your device. If you see (white), Bluetooth is on and a device is connected to your iOS device. If you see (gray), Bluetooth is on but no device is connected. If you don't see a Bluetooth icon in the status bar, Bluetooth hasn't been paired with any devices. You can also see which Bluetooth accessories are paired with your device, and whether they’re connected. Tap Settings > Bluetooth, and look under My Devices. Disconnect a Bluetooth accessory To stop using a Bluetooth accessory with your device, you can either turn off the accessory or unpair it. Turn off a Bluetooth accessory If you turn off a Bluetooth accessory, it will still be paired to your device but you’ll need to turn it on again to use it. Unpair a Bluetooth accessory To unpair a Bluetooth accessory, tap Settings > Bluetooth, find the device you want to unpair, and tap , then Forget this Device. When you Forget this Device on your iPhone, iPad, or iPod touch, that accessory is removed from the list of available Bluetooth devices. To add the Bluetooth accessory to your device again, place it back in discovery mode and repeat the steps above to pair it again.