How do I change the symbol which is displayed with the bluetooth device? For example the below one has heart shaped symbol.
Try changing the appearance value you send when advertising.
you can find the Bluetooth SIG defined appearance list in https://www.bluetooth.com/specifications/gatt/viewer?attributeXmlFile=org.bluetooth.characteristic.gap.appearance.xml
Also, see this link. Search for "appearance".
Thank you Jing & Edvin. This feature is so cool!! What if I want my own symbol? Does it need to registered or something? Of course it will come under the reserved category.
It is not possible to create a custom symbol. These are not transferred over the link, they are stored in the phone (or whatever scans the advertisement packs), and only the appearance ID is transferred. So it will differ from phone to phone what the symbols look like.
You can see a list of the BLE appearance symbols in ble_types.h in the SDK, or on the website for Bluetooth.