Some questions about CodeLess

About CodeLess, I also want to know the following information:
1. How to modify the device name, in the user_config.h file, I found #define USER_DEVICE_NAME, but after I modified it, it did not take effect, and I did not see any information on the UM-B-140: DA14531-DA14585 CodeLess page How to modify the device name, please tell me how to modify the name.
2. I want to know which function is mainly used to send the data received from the serial port to the mobile phone APP via Bluetooth. Please tell me the name of this function.

3.I want to know which function is used to receive the serial port data. I want to understand the connection between them. You can tell me some key codes, which will provide me with ideas.
4. I want to use the SUOTA function, what information should I refer to? Or how should it be done?
Thank you very much!