Are URI scheme requirements/standards unique to each platform?

I'm wondering if the standard/requirement ends after the colon/double forward slash "://" of the URI?

I will use the Facebook mobile app as an example. It is a multiplatform mobile app. If you wanted to create a QR Code that links people to your page, you have to have two different QR Codes to work for iOS and Android platforms.

The iOS platform URI scheme is "fb://profile/" to open a page in the Facebook iOS app. However, the Android URI scheme is "fb://page/" to open the same page using the Facebook Android app.

Do platforms dictate the URI scheme past the colon/double slash? Is it a requirement/standard?

CodePudding user response：

The apps define what comes after the scheme. Every app will define it however they think is convenient. In the Facebook case, what happened is the team that did it in iOS didn't talk to the team that did it in Android, and because of that it isn't consistent.