It's no accident that Apple chose a yellow icon for its walkie-talkie feature. I dug out my old (2002ish) Nextel with PTT (push to talk). It was all the rage back then... :
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Remember these weird cell phones from 2005 that were also walkie talkies? Super annoying. : r/nostalgia
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TOAN MAGAZINE — Throwback Thursday: Nextel/Boost Mobile Chirp...