1. Text Viewer Capabilities

Maru supports a wide array of text-based formats including TXT, CSV, SMI, SUB, and SRT files, making it perfect for reading subtitles or structured text documents. It also offers robust EPUB support, displaying both text and images seamlessly, with built-in font options for a personalized reading experience. The app allows for direct opening of compressed text files such as ZIP, RAR, 7Z, and ALZ/EGG. Users can customize fonts—including san-serif, serif, or even upload their own—adjust font size, spacing, and margins. The character encoding can be switched between Auto, UTF-8, and others to ensure proper display of international characters. The appearance of text can be further tailored through background colors, background images, and text colors. Navigation is flexible with arrow buttons, screen taps, drag gestures, and volume buttons. Page flip effects like slide, scroll, and animation add to the immersive feel. The app also provides quick navigation tools, a bookmarking system, text-to-speech with language and speed controls, and even a slideshow mode.

2. Comic Viewer Support

The comic viewing features elevate Maru to a new level, supporting popular image formats such as JPG, PNG, GIF, BMP, WEBP, TIFF, HEIC, and AVIF. Compressed image archives (e.g., ZIP, RAR) are also supported with streaming capability, allowing for efficient access to large comic collections. The app provides a zoom capability of up to 8x with sharpening options and supports double compression. It caters to different reading styles with left-right or right-left navigation for Japanese-style manga, landscape dual-page view, and smooth scrolling animations—ideal for webtoon enthusiasts. Features such as automatic image rotation, support for animated images like GIF and WebP, and manual rotation options enhance visual flexibility. Users can apply filters—such as inversion, sepia, and sharpen—and crop image edges for better focus. Quick access navigation, bookmarking, slideshow, and zoom functions ensure a smooth and customizable reading journey.

3. File Management and Organization

Maru offers comprehensive file management tools that include coloring read history markers—red for recent, green for partially read, and blue for completely read. You can preview images in various sizes, sort files by Name, Size, or Date, and perform operations like delete, rename, copy, or move. The app supports manual uncompression of archives and integration with external storage devices such as USB with support for FAT32, NTFS, and exFAT filesystems. Search functions enable locating files by name, content, or pictures. The app also allows manual file browsing and management, syncing with cloud storage, and supports FTP, SMB, WebDAV, Google Drive, Dropbox, and OneDrive for seamless content access.

4. Additional Features and Customization

Maru provides a wide range of personalization options including themes, colors, and multiple language support—Korean, Chinese, Japanese, English, and more. It offers synchronized reading histories across devices, ensuring you pick up exactly where you left off. Secure features like password lock help protect your content. For Samsung users, compatibility with S-pen enhances page navigation and slideshow control. The app also supports headset and media buttons for controls like pausing slideshow or toggling Text-to-Speech. Backup and restore functions preserve your settings, while shortcut management allows quick access to frequently used apps and functions. Advanced file transfer protocols like SFTP and WebDAV facilitate secure remote file access, making Maru a comprehensive solution for digital reading needs.