You should update your passwords regularly to keep your accounts as secure as possible. This article explains how to change your Gmail credentials in the app for Android 4.4 or later and iOS 11 or later.
How to Change Your Gmail Password – iPhone & Android Phone
To change your Gmail password on an Android smartphone or tablet, follow these steps:
Tap the hamburger menu (the three horizontal lines) in the top left corner of the Gmail app.
Tap Settings from the drop-down menu.
