How to set BLE client name?

I am not sure about GB. I've made test "Current Time" GATT server, and it works.

Regarding roles. In the standard L&N GATT it is specified:

https://www.bluetooth.org/DocMan/handler­s/DownloadDoc.ashx?doc_id=271996
BLUETOOTH PROFILE SPECIFICATION Page 8 of 32

Location and Navigation Profile
2 Configuration
2.1 Roles
The profile defines two roles: LN Sensor and Collector. The LN Sensor is the device
that reports speed, distance, location, elevation, and/or navigation data to a Collector.
The Collector is the device that receives the data from a LN Sensor while connected to
a LN Sensor.
The LN Sensor shall be a GATT Server.
The Collector shall be a GATT Client
...

• The LN Sensor shall use the GAP Peripheral role
  
  

So, it looks like I've architected my apps correctly :)