I couldn't see the theme option. Not sure if t-Mobile disabled it or what because I would find it just fine on my g2. Then I came across this http://androidforums.com/lg-g3/859027-cannot-access-themes-option-in-menu-solved.html the 2nd post helped me. Also download LG smart world to choose different themes. The g2 came with two themes but the g3 just one.