The Wikipedia portal includes a URL that points to the English Wikipedia article List of Wikipedia mobile applications.

For other languages it may be changed by translatewiki translators to any other URL, on Wikipedia or outside it, but it's not a very good solution. Also, while translating Wikipedia articles is possible using Content Translation, such a thing should function more like a tightly structured list and not so much a Wikipedia article.

I have a couple of proposal to handle this better.

One: Create a translatable page
In this option, the maintainers of the portal will collaborate with the PMs of the mobile apps to create a translatable page on Meta or mediawiki.org. This page will include a list of all the apps that the PMs and the portal maintainers want the portal readers to be aware of. This may include non-WMF apps, as the current article at the link target does. Like the current article, it will be editable by the editors community.

Once the page exists, change the URL in the translatable message Portals-app-links.url to point to this page. Or even better, remove it and get it to point automatically to the current language if it's available.

Two: Integrate the list into the portal itself
Just remove the URL, and write everything that you want the users to know about the apps in the Portal's UI itself.

This may require a bit more development work, but may prove to be easier for the translatewiki translators, who will be able to do everything in one place.

Another possible disadvantage is that it will be less easy for the editors community to change this list.

I've subscribed all the mobile apps PMs because they should probably be the people who want to communicate about their apps to the public, so they should coordinate the content of this page with each other.