How to mention users with “@” in app like Instagram

Question

I am creating an app that has photo sharing, and I am trying to add in the functionality to mention (or tag) users. Twitter is what originally starting using \"@\" with a userna

Answer 1

Listen to the input on iOS. When the user types an @, followed by a character, make a call to an url on your server (/user/lookup/?username=joe for example) that routes to a view which looks up up users beginning with joe. Return it as json and display it in a dropdown.

Source: How to mention users with "@" in app like Instagram