Open Castro links in the app, not the in-app browser
When you share a Castro link on social media, it opens in a slow in-app browser where your fans aren't logged in. OnLynk fixes that: your link opens straight in Castro, ready to go.
The in-app browser problem
Instagram, TikTok and other apps open your Castro link inside their own webview. It's slow, your fans aren't logged in, and many give up before they act.
How OnLynk opens Castro
OnLynk detects Castro and the visitor's device, then opens your link directly in the Castro app where they're already logged in. One tap, no friction.
No app installed? No problem.
If Castro isn't installed, OnLynk opens the visitor's own browser (Safari, Chrome) instead of the social app's in-app browser, so they still arrive logged in, with their session intact.
Works with links like
https://castro.fm/...
Open your Castro links in the app
Create your OnLynk link in two minutes. Free plan, no card.
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