# Customizing eBook UI

**Note: in 3.4 we changed the eBook rendering engine and this customization is no longer possible.**

Sumatra has 2 UIs:

- one for PDF/DjVu/Comic Book documents
- another one for eBook documents (ePub, mobi etc.)

As of version 3.1.2 eBook UI doesn't have zoom (changing font size), text selection etc.

There are 2 ways to customize eBook UI.

## Use advanced settings

Use **Settings -> Advanced Settings** menu and find **EbookUI** section.

As described in [settings](https://www.sumatrapdfreader.org/settings/settings) you can change the following aspects of eBook UI:

- FontName
- FontSize
- TextColor
- BackgroundColor

## Use PDF UI for eBooks

Use **Settings -> Advanced Settings** menu and find **EbookUI** section.

Set **UseFixedPageUI = true**

Restart the app after changing the settings.