There is a website called url genius.
How it works: you choose Instagram for example, you write your profile link, and then it creates a deep link, when you click on it either you're on iPhone or Android, it open directly the app WITHOUT ASKING "DO YOU WANT TO OPEN THIS LINK IN THE APP"
I tried to replicate this with some JS, my code first detect which device the user is on, then :
if the user is on Android it redirects with a window.location.replace to intent://www.instagram.com/profile/#Intent;package=com.instagram.android;scheme=https;end
if the user is on iPhone it redirects with a window.location.replace to instagram://user?username=profile
MY PROBLEM:
The link doesn't open directly in the app, it first asks to the user "do you want to open the link Instagram app". So how does URL Genius manage to redirect directly the user?