Most protective screen films require precise alignment, which can sometimes be difficult and result in less-than-perfect results. PureGear's PureTek Roll-On Screen Shield Kit for iPhone 5 ($25) removes that element, thanks to a large applicator contraption: the packaging doubles as the installation tool. You simply lay your iPhone 5 in the tray, run a roller down over the screen, and remove a protective sticker. In our initial test, we found the alignment…