(Posted this on Reddit already, but I thought it might be interesting for you guys)
Hey everyone,
This little gem I made uses the Telegram Bot API to easily send notifications to your users via Telegram. As soon as a user starts your bot (via a link in your app), they are stored in the database, giving you the ability to send notifications at any time.
For more information (including a demo app!), check out the GitHub page. Also, for any questions, tips or other thoughts, feel free to contact me on Twiiter :))