FBReader ComicBook plugin is exactly what its name suggests: an app that, once installed, lets you read comics in CBR and CBZ format on your Android. The plugin has been developed by the same team as FBReader, so it's guaranteed to work.
Since its a plugin, FBReader ComicBook plugin won't change the default FBReader interface. In fact, you won't notice any change at all until you try opening a CBR or CBZ file. Then you can see the cover, name, author, and the language in the preview.