When is a custom GATT profile recommended?

[Mahesh Venkitachalam]

I am currently developing an IoT device using nRF8001 which needs to report gas concentration obtained from a sensor. I have looked through the standard GATT profiles, and I don't see anything I can use directly. I was curious if it's common practice for products to create their own custom GATT profiles.

[Dhruv Agarwal]

Hey I have worked on nRF51822, and yes you can easily create your own GATT profile. You can start by using code from existing standard GATT characteristic code. I have used mbed's APIs mbed-src,BLE_API, (there is one more for nrf51822, but you gotta find compatibility for your chip and board). A simple way to get idea would be reading this simple code.

github.com/.../BatteryService.h

I will put my sample code to use it on github and will update here asap if you want.

[Mahesh Venkitachalam]

Thanks, @dhruvagga. My question was more on best practices - whether it is better to define your own, or try to use existing profiles. I don't see anything existing for measuring ppm of a gas for example. Such scenarios must be common for industrial applications?