A phone icon crossed out — signage for "turn your phone off/silent," seen at movie theaters, hospitals, and libraries. On social media people repost it literally to remind others of phone-free zones, or ironically caption it while clearly posting from their phone. It belongs to the same 2010 batch of literal signage emoji as the no-pedestrians symbol, imported wholesale from public information pictograms.
Keywords: cell, forbidden, mobile, no, not, phone, phones, prohibited, telephone