Perfect Viewer vs Bookshelf Usage & Stats

Perfect Viewer is a very fast image/comics/ebook viewer. *Turn black/white image into 4 colorize image(Only available for donated users. Need install Perfect Viewer donation application). *Page layout: Auto single page, Auto dual page, Auto switch by screen orientation *Support eEook file format: EPUB, HTML, TXT *Support image file format: JPEG, PNG, GIF, BMP, WebP, TIFF *Support archive file format: CBZ/ZIP, CBR/RAR, 7Z/CB7, LZH, CBT/TAR *Support PDF, XPS & DJVU file after install the PDF plugin *Open file from network file sharing(CIFS/SAMBA), FTP, SFTP, FTPS, OPDS *Require internet permission for CIFS/SAMBA support. *Support open files from Google Drive, Dropbox, OneDrive after install the source plugin *Require "GET_ACCOUNTS" and "USE_CREDENTIALS" permission for Google Drive support *Support 3 viewer mode: Page mode, Vertical scroll mode (PDF viewer,webtoon like) and Horizontal scroll mode. *Smooth filters: Averaging, Bilinear, Bicubic, Lanczos3; *Five view mode: Full size, Fit Screen, Fit Width, Fit Height, Fixed size, Stretch; *Support Left-to-right & right-to-left reading *Set image as wallpaper *Browse image in folder/archive as thumbnail *Bookshelf function *Support pinch to zoom & fling gesture *Simple bookmark function *My favorites management *Cache next and previous page *Simple file management(delete, rename) *Slideshow *Support extract files from archive *Adjust image brightness,contrast & gamma *Auto cut off white border. *Support Google Chromecast *Balloon magnifier