Guides
Short, practical answers about phone verification, written by the team that runs the SIM cards.
What is a non-VoIP number?
A non-VoIP number belongs to a real SIM card on a mobile network. Here is how apps tell the difference, and when you need one.
Read the guideHow to sign up for Telegram without your own number
Telegram needs a phone number to create an account. Here is how to use a real SIM number instead of your own, and how to keep access afterwards.
Read the guideWhy WhatsApp rejects virtual numbers, and what works
WhatsApp blocks many VoIP numbers at sign-up. Here is why, what a real SIM number changes, and how to keep the account once it's created.
Read the guideSMS code not arriving: what to check
The usual reasons an SMS code doesn't arrive, from typing the number wrong to the app sending it somewhere else, and what to do about each.
Read the guide