Instagram app lock

With the phrasing of your question and particularly the scope of your involvement here—whether as end-user, app developer, an interested app user sent this way from Instagram—is unclear.

First, to clear up what may be some confusion...

We’re not folks that work for Apple. We’re other users. Neither iOS, nor iPadOS, nor Face ID, nor Touch ID, is “mine”. Folks from Apple may or may not read replies here, too.

As for selecting alternative hardware, if Samsung devices running Android—or some other hardware and software—works better for your requirements, you should absolutely use that.

An app developer can choose to implement Face ID or Touch ID locking, and it’s up to the app developer to add that Face ID or Touch ID support. I have had a third-party app installed that does exactly that, too. This beyond Safari logins and related, as arises logging into ASC.

If you’d like to suggest to the folks at Apple to add a user-configurable app-lock mechanism requiring Face ID or Touch ID independent of the app developer support (or the app developer lack of support) for Face ID or Touch ID: Product Feedback - Apple

I’d expect that the Instagram app developers will be able to add this authentication support well before Apple might roll out changes and support for retrofitting app authentication in some future iOS or iPadOS release. This if the folks at Apple decide to add that feature, of course.

Now if you are an Instagram app developer or other app developer for some other app and wish to integrate Face ID or Touch ID into your iOS or iPadOS app, there exists documentation, and there are various examples posted around. There are also the developer forums, if you’re stuck with some app design or app coding confusion.

Based on a very quick search for details on implementing Face ID and Touch ID:

https://developer.apple.com/documentation/localauthentication/logging_a_user_into_your_app_with_face_id_or_touch_id

https://www.pluralsight.com/courses/face-touch-id-authentication-ios-swift-5

There’s also work happening in Safari:

https://appleinsider.com/articles/20/06/24/new-safari-api-enables-face-id-and-touch-id-authentication-for-websites

But again, web service authentication and app-related authentication features, requirements, and enhancements are all details that the app developer has control over. Not Apple, not me, not anybody else around here...

You asked a terse question. You got a terse answer. No impoliteness was intended.

Ask Instagram support. Their app, their security.