LG Optimus G - Manual (Page 39)

Phone Basics 31
2. Tap the application icon again and select the a desired icon design.
– or –
Tap Create photo icon to take a new picture or select a picture from the Gallery.
Access Recently-Used Applications
Your phone keeps a running list of your most recently used applications.
1. Touch and hold to open the recently-used applications window.
2. Tap an icon to open the related application.