Best practice retrieving Telegram ID about telegram HOT 3 CLOSED

You can make use of the Deep linking feature Telegram offers.

Generate a unique token, show them a link and let the user start the bot with it. Once you get the start payload, you can associate the Telegram account with the user's account in your app.

Just make sure you revoke that token after associating the accounts. If the user wants to link to a new account, you can generate a new token (perhaps it could expire when the entire process is done so it's always unique).

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Appreciate you thinking along, thanks for the inspiration!
I'm assuming this will require me to use the SDK instead. So I'll look at that one now.

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In addition to the above, if you want to have the user confirm the opt-in (or rather double opt-in), you can perhaps show them a nice response from your bot as soon as you get the start payload telling them if they're sure they want to link this Telegram with the account in your app for notifications and an inline button with a callback query to confirm the same so it's easier to process or you could have an expiring external link too (again with a unique token).

While this isn't really required but it'll be more explicit in case if the user wasn't sure when they just clicked on the bot link in your app. Just an idea.

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