Is it possible to develop an iOS app with bluetooth capabilities?

Would the following be possible?

Let's say I have a scale with Bluetoot开发者_如何转开发h capabilities, when I turn it on, it sends the weight via BT.

Is it technically possible to develop an iOS app which pairs with the scale and receives the data from it?

According to Apple:

Technical Q&A QA1657: Using External Accessory framework with Bluetooth devices.

Q: I understand that the External Accessory framework in iOS 3.0 and later will allow my application to communicate with Bluetooth devices. So why doesn't my application see the Bluetooth accessory sitting next to my iPhone?

A: The External Accessory framework is designed to allow iOS applications to communicate only with hardware accessories that are developed under Apple's MFi licensee program. MFi compliant accessories can be implemented as wired devices, meaning they plug in to the Apple device's 30-pin or Lightning connector, or as wireless devices, whereby they use Bluetooth as the communication channel. Either way, an application that uses the External Accessory framework will not be notified of an accessory's presence unless the accessory identifies itself as being MFi compliant, i.e., it was specifically designed to interface with an iOS application.

Yes, we can connect Bluetooth devices with iOS application through Core bluetooth framework. This framework is supported on the iPhone 4s, iPhone5,iPhone 5S ,iPad3. We can use BLE 4.0 for the communication between scale and iOS application. Here, iOS application become the client and scale become the peripheral. You Can set as well as get data from the weighing scale.

While the External Accessory Framework with Bluetooth is one of the possible solutions, it has additional requirements to be built as per Apple MFi, here Bluetooth reference is to the Classic Bluetooth (Version 3.x and below)

The best solution for the use case you have defined is to use the Bluetooth Low Energy (LE) (aka Bluetooth Smart) technology (Bluetooth 4.0) and it is available to applications as part of the Core Bluetooth Frameworks Here are the APIs for Core Bluetooth that applications can use.

While currently Bluetooth Low Energy is supported on the latest iPhone 4S, New Mac Mini & Macbook Air - its expected most new Apple & Others hardware will have this standard.