pwall is modern style photo/video viewer and organizer.
It shows the folders of your photos/videos main directory in the left pane and a photowall in the right. The photowall is a scrolling panel of square thumbnails giving a preview of each photo/video.
Loading and unloading of this scrolling panel is made dynamicaly, viewing page by viewing page like smartphones do.
It also allows you to have basics management of photos/videos (change dates, copy a group of photos to another directory, delete, share, get GPS data...). Clicking on a photo/video opens it in fullscreen mode. You can continue your navigation in this mode with left and right keys. I use it as an alternative to Shotwell.more...

Download the .deb file (release tab). It has been tested in ubuntu 16.04, 18.04, 20.04 and has been built over the GTK 3 framework.
To enjoy all the features, you also need to install jhead, ffmpeg and gstreamer libraries
with sudo apt install jhead ffmpeg libgstreamer1.0-0 gstreamer1.0-plugins-base gstreamer1.0-plugins-good gstreamer1.0-plugins-bad gstreamer1.0-plugins-ugly gstreamer1.0-libav gstreamer1.0-pulseaudio
To install the .deb file, run sudo dpkg -i pwall-x.x-x.deb (where -x.x-x is the version you've downloaded).
If you've got dependency errors run sudo apt install -f

You can also build and install a package with the makefile located in the src dir. With a terminal, goto this dir and run make then make install