To automatically update Blender, Gimp and Inkscape to the latest and greatet version in Ubuntu

All you need to do is open Terminal and paste these codes:

Gimp

sudo add-apt-repository ppa:otto-kesselgulasch/gimp
sudo apt-get update

sudo apt-get install gimp 

Blender

sudo add-apt-repository ppa:irie/blender
sudo apt-get update
sudo apt-get install blender 

Inkscape
sudo add-apt-repository ppa:inkscape.dev/stablesudo apt-get update
sudo apt-get install inkscape-trunk