I'm not saying you shouldn't rock an Attack on Titan phone case in the shape of the 3D Maneuvering Device's controller from the show. By all means, let your otaku flag fly. All I'm saying is: don't pull this thing out on public transport if you don't want get arrested and/or shot. Because it looks exactly like an IED detonator.
The case itself is very cool. It's a faithful adaptation of the device from last season's monster anime hit (and massively popular manga) Attack on Titan and is available from Strapya World for roughly £22.50 for iPhone 5c and 5S models. The outer trigger opens a shutter to enable your phone's camera.