sudo add-apt-repository ppa:tobias-quinn/gsmz
sudo apt-get update
sudo apt-get install gnome-shell-mousewheel-zoom
Now you will need to restart Gnome Shell by pressing Alt+F2 and then “r” and Enter. Some of you may need to restart your operating system so that mousewheelzoom.py may run on startup.
After this you can zoom anywhere (desktop, windows etc) by pressing the left “Alt” + mouse wheel!