You can change your password from your profile on both the web application and the smartphone application. Your password is case sensitive and must have a minimum of 6 characters. (Helps keeping your account safe)
It's a one-two step process, first go to "My profile" by clicking on your picture / initials, second change your password!
It's a 3 steps process,
Click on the menu on your top left
Chose My Profile
Go to the bottom
Change your password