Most laptops and cellphones have smooth surfaces like glass or durable smooth plastic around the cameras, and if you're one of those people, they won't work for you. Adhesion is terrible, the lid slips and slides. If you also actively use your laptop or phone, forget it. I don't know how they behave on rough surfaces. Another reviewer can probably provide that answer. As for the ability to close the cameras while still allowing the camera to do its job, as long as those things don't last, you're covered.
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