Telegram recently launched the new Payments API (https://telegram.org/blog/payments). Thanks to this API bots can provide complete checkout experience for users. A user can purchase a product not leaving Telegram messenger.
I am developing a Shopify sales channel app to sell products on Telegram messenger. The app is fully operational and I would like to test it with a real store owner. If you are interested in selling products on Telegram, please send me a message at firstname.lastname@example.org