Simple! Click on the Avatar Icon on the top left --> My Info & Settings to change your password. In case you have forgotten your existing password, you will need to reset it from the login page.
If you are on an older Android version of the app (3.29.0 or less), you will see ‘ME’ section instead of the ‘Avatar’ Icon. Click here to update to the latest version of the app.
Learn how to set a strong password by clicking here