Using Notes
When you talk/discuss with the customer/partner and if you need to report to your boss/colleague, use @mention method to report. Type @ then name of the person to inform as below
https://gyazo.com/38f102de0ca07aeb1ec36df45df5c960
Then type necessary message
https://gyazo.com/7b92577e72eec0d623b931e0fcfc03f6
After Save note, notification will be sent by email to the person in charge.