Q: iPhone bluetooth can connect any different company's product such as Nokia,Samsung  and other companies ?

File transfer, by Bluetooth, has never been supported on any iPhone. So, you won't be able to pair with other phones or computers. You can only pair with a computer for the singular purpose of Tethering, nothing else.

If you mean other phones... This is not natively supported...

See the Article you posted from as to the supported Bluetooth profiles for the iPhone.