Under 'Settings' you will find access to preferences. Scroll down to Global Shortcuts.
Keyboard commands are editable by clicking on the input box. The defaults for in-conference are shown below:
Quick Drop in
Hit the command + D to see a team directory open — arrow up/down to a teammate, tap, and you're in a Drop-in!
You can create a shortcut for any team member (example above: Command + F will Drop in on Fatima)