Correct way in 2018 to open Facebook app via website link?

Question

Let me say first that I\'ve researched this for the past 4 hours. From various threads, I have seen that linking to fb://page/PAGEID is the OLD way of

Answer 1

Now it's changed to:

For iOS: fb://profile/PAGEID

For Android: fb://page/PAGEID

PAGEID is the numeric pageid that the page owner can see in the about box in facebook