ستتمكن قريبًا من استخدام ماسنجر دون الحاجة إلى حساب فيسبوك

I think there’s a challenge/flaw with this one. What if a prepaid number was used to enroll to the FB’s Messenger feature/app? What if he/she floods or spams FB users with it and eventually disposed that sim card for it to be unable to be tracked. What if again, if the mobile phone was stolen with a prepaid sim card? he/she will gain access to the messages? What if again, if all of the possible worst scenarios will happen and the original user no longer uses/have that mobile number? Philippine Telco companies tends to recycle the mobile numbers that they distribute. What if a 1 mobile number/service provider will be provided to each individual or at least register all sim cards/mobile number for every individual?