This is one of things I’d love to implement if I ever get around to creating a proper iOS app! No promises on if/when that might happen though. (AFAIK it’s not possible at the moment for a web-app to add a target to the iOS Share Sheet)
On desktop Chrome there is a quick way to import articles using the Readlang Chrome extension.
Right click anywhere on the web page you’d like to import and click the “Import to Readlang” option:
You could import a bunch of articles this way while at your laptop so that you have a queue of stuff to read later at readlang.com on your phone (maybe even in full screen mode as a PWA).