Ask HN: How can mobile app developers take credit for their work?

I've spent the past year building a (complex) mobile app for a client and we've released it to Play Store. Currently, none of my branding is on the app. When people find the app, there is no connection to me, the Developer of the app.

As a freelancer, I want to be able to put this app in my portfolio to attract future prospects.

How do app developers usually take credit for their work? Websites usually credit the creator at the footnote at the bottom, but I don't see any such etiquette in mobile apps.

Is there an obvious/subtle solution?