I'm making my own smart link page:
https://www.hooklust.com/oo.a/
(only part way through - ignore the horrible styling)
and can get the Spotify link (top green button) to open the song in the Spotify web app, but how is a service like this...
https://songwhip.com/hooklust/sekai-heiwa-world-peace
able to prompt to open the Spotify app after the Spotify link is clicked please? When I click theirs, I see the "Open Spotify - https://songwhip.com wants to open this application." prompt.
Thank you
One way to open the link directly in the app is to use the URI instead of the URL, e.g. in your case link to spotify:track:2bmgv7q8RgC0NgF9SlGlpe instead of https://open.spotify.com/track/2bmgv7q8RgC0NgF9SlGlpe:
<a href="spotify:track:2bmgv7q8RgC0NgF9SlGlpe" target="_blank">