@slightlylate interesting app capability wrt whether phone numbers are good instruments for user identificationpic.twitter.com/TvwF9kJuJL
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: hrm....is that device-based knowledge? Or something on the FB/carrier side?
I believe it's fb/carrier, not client
Twilio offers this ability. Youd need to poll though, cant be notified of the change - https://www.twilio.com/lookup
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