Most plastic shells that we test, whether they have a glossy or matte finish, are flat. SmartJacket’s back instead has a 12 by 18 grid of shiny raised squares that looks and feels pretty cool, adding some flair without extra bulk. It’s not the absolute best shell in terms of coverage, since it’s lacking button and speaker protection, but it’s pretty good. Port openings are large enough to accommodate any accessories, and the…