I have an iPhone 4S and I would like to connect it via Bluetooth with an iPhone 5 but it won't connect.
How can I connect them?
iOS uses Bluetooth in a very particular way. Depending on what you want to achieve, you can use an App or an iOS feature:
Typically, iOS pairs only with accessories such as bluetooth headphones or heart rate sensors.
There are other bluetooth features that are managed by iOS and work without user intervention such as continuity or bluetooth beacon detection.
The Bluetooth on iOS devices does not work for pairing or file sharing. It can be used for Airdrop and peripherals such as bluetooth headphones. You can cannot pair them as you can do with Android devices.