Reading sensor data from nrf52 in ios

[Soul Blaze]

So I am using nrf52832 and making a whole new app in ios. My objective of the app is to get the sensor data (specially motion sensor data and accelerometer data) which is connected to nrf52832. So far I have reached the stage where I can scan the device, connect the device, disconnect the device, send text message from app which is received by UART. I referred nRF Toolbox ios app. The sensor data is received in nRF Connect ios app but is not open source. The nRF SDK might have the code but it's purely in C and it will not be much help for me. While reading Core Bluetooth Documentation of Apple, I did come across topic : " Explore a Peripheral's Data Wisely and Subscribe to Characteristic Values That Change Often ". But I am not quite sure if I am on right track and if I am where should I be putting that code in my existing project.
I have been trying all possible ways and yet didn't find a solution. 

Just for understanding I am coding in Swift 4.

Any sort of help, guide, step, way is very much helpful and appreciated. 

[awneil]

The whole point of Bluetooth is that it is standardised, and not dependant on the target hardware.

So your iOS app neither knows nor cares about the Nordic chip.

What your iOS app interacts with is GATT - so that's where you need to be focussing you searches.

eg, https://www.google.co.uk/search?q=ios+swift+gatt

[Soul Blaze]

Thank you so much for writing and helping me out. It really was neecessary for me to check if I was on going proper.
I searched on the same thing and it seems Characteristics value was indeed the right track, but I wish to get accelerometer data and motion sensor data neither of which have a UUID registered as primary service. How do I go ahead with that?

[awneil]

You will either have to define your own custom service, or adopt something "generic" - such as the Nordic UART Service (NUS).

Have you looked at how the Nordic Thingy does it ... ?

[Soul Blaze]

Yes, I did but the framework of Nordic Thingy is different than the one I am using and results in code clashes which is why I am trying to avoid that. 

[awneil]

I said "look at" - not "copy"

[Bjørn Kvaale]

I would suggest downloading the Nordic thingy FW & taking a look at that first. The documentation provided here could also be helpful. Then, I would download the Thingy app source code (written in Swift 4.0) & see how the smartphone side implements this. In essence, exactly what awneil said. It might also be useful to take a look at some of the easy tutorials on devzone (this & this). 

Even though the Nordic SDK & Thingy SDK are written in C, I believe you can learn a lot by understanding what the main code snippets are doing.

[Soul Blaze]

Bjørn Kvaale and awneil Thank you so much for taking in time to help me. I was successfully able to complete what I was searching for from days. awneil I did have a look at how it worked but it was completely in some other direction and also I wasn't able to connect the dots. So I figured out by understanding the documentation of Core Bluetooth and GATT. What I came to know is that it uses UART over BLE which Core Bluetooth Framework already has it inbuilt. Apart from that Characteristic UUID and Service UUID must be known before communicating with the sensor inorder to get values from it.