FastStone Image Viewer, IrfanView, digiKam, ACDSee Photo Studio, XnView, ImageGlass, XnView MP, Shotwell, Preview, nomacs, Fragment image viewer, FastStone MaxView, Diffractor, FotoStation, Eye of GNOME, JustLooking, Xee, photos2webgallery, Xviewer, Sequential, Picturama, F-Spot, eye of MATE, Fototriever, JPEGView, Basic Photo Viewer, PolyView, qimgv, Image Detail, ViewPic, WildBit Viewer, ImgV64, gimmage, CocoViewX, RoloViewer, First Impression, Rest7 Online Image Converter, GLiv, NexusImage, GQview, Maverick Photo Viewer, GImageView are some alternatives to Gwenview.