For Android, I'd recommend Lithium with my
patches, which adds:
- Custom icon color.
- Custom cover aspect ratio.
- Optional cover-only grid view.
- Debuggable reader webview.
- Offline dictionary.
- Custom fonts. (I really like Equity btw)
- Smaller minimum font size.
- Additional information in the reader footer.
- Series metadata support.
- Series section in library drawer.
- Increased number of visible actions for the reader toolbar.
- Support for inverted portrait/landscape rotation.
The main disadvantages are that switching chapters is a little bit slower than I'd like due to how it works (it has to compute pages before making the content visible), and it only supports EPUB.