Actual zooming of content applies to some texts, for example, message viewers and editors, and some list components.
There are two types of zooming, depending on the type of content:
Text size adjustment should be available for text content without a strict layout, for example, in email. When text size is changed, the text will be rewrapped to fit the width of the view. Seeing all content may require more vertical scrolling, but the intention is to avoid the need to scroll horizontally. The number of available text size levels may differ from application to application.
With content that does not allow reformatting, such as images, maps, PDF documents, and many web pages, zooming changes the size of all content, keeping the aspect ratio of the content unchanged. As the layout does not change, zooming may lead to scrolling vertically and horizontally to see all content.
Whenever an application starts, the text/content size should be the default as defined in Settings. Each zoom adjustment the user makes is temporary, meaning it will be discarded when the application is exited.