iOS Question Bluetooth chat with Desktop or Mac or Android

[exorionMember]

Hi guys,
I want to develop a bluetooth chat application for iPhone.This app will be send and read data.But I can't any solution or example.All pages says "You can't do this, it's imposibble".Maybe anyone help me.
I use iphone 4s.Thanks for every one.

 

[Erel]

Classic Bluetooth is not open for developers in iOS.

You can use BLE as in this chat example: BLE Chat - Connecting Android and iOS