Telegram has launched a login widgetfor websites aimed at enabling communication between businesses and users.
According to Telegram, “When you use Telegram login for the first time, our widget asks for your phone number and sends you a confirmation message via Telegram to authorize your browser,”
“Once this is done, you get a two-click login on every website that supports signing in with Telegram.”
Logging in will send your Telegram name, username, and your profile picture to the website owner. Your phone number remains hidden

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http://infocity.com.ng/2018/02/telegram-introduces-login-widget-to-let-website-owners-chat-to-users.html