iOS 9 has made sharing Bluetooth devices with more than one iOS device much easier. In previous versions of iOS, you has to either disable Bluetooth on one device, select “Forget This Device” in Settings and come back later and go through the steps of reconnecting a “new device” when you wanted to use it again.
iOS 9 makes it much easier to switch which iOS device is connected to a single Bluetooth accessory. Here’s how to temporarily disconnect your iPhone from a device.
Open the Settings app, and tap on the “Bluetooth” menu option.
Find the device you want to disconnect from, and tap the Information icon. (That’s the blue “i” in a circle on the right hand side of the device’s name.)
In the device’s information screen, you’ll see an option to “Disconnect.” Tap this, and your iPhone will disconnect from the Bluetooth accessory. (You can also opt to “Forget This Device,” but that’s what we’re trying to avoid in this how to.)
Now, the Bluetooth accessory is freed up for another iOS device to connect to.
When you want to reconnect, just follow the steps above, but tap on the device’s name, (which will be marked as “Not Connected”), and your iPhone will reconnect with the accessory.