Android comes with a lot of interesting hotkeys that will take you directly to the appropriate applications. For instance, tap on Search + B launches the web browser while Search + E launches email.
However, it is possible to set your own keyboard shortcuts for any of the default apps or set new shortcuts for the apps that you have installed. To do this, navigate to Main System Settings -> Applications. Here, select “Quick Launch“.
You will now be shown a list of existing keyboard shortcuts. Modify those that you need. You may also add new hotkeys for your favorite apps here.