Phototonic is a fast and functional image viewer and organizer, inspired by the traditional image viewer design (i.e. thumbnails and viewer layouts).
Phototonic is released under GNU General Public License v3.
Source Phototonic Homepage:
To install just run the following commands via your systems Terminal.
sudo add-apt-repository ppa:dhor/myway
sudo apt-get update
sudo apt-get install phototonic