When viewing a single image on a phone, there's no way to perform another search without first gling back to "Posts". The desktop version has the search box in the upper-left, shouldn't the mobile version also have one, either above the image, below the image, or below the comments?

I normally just have the mobile layout disabled, but this does seem strange to not be there. It doesn't take up much space on the mobile layout compared to some of the other things.