Two ways: use Import from Lightroom in the app, same as Lightroom Classic or desktop users — Lightroom mobile syncs to the same Adobe cloud catalog, so those photos show up there too, and this way correctly tracks which ones you've already imported. Or use Lightroom mobile's own Share button and pick BirdfolioSA directly. That also works, but has a known limitation right now: photos brought in this way aren't yet recognised as “already imported” by the filter, so take care not to import the same one twice. It's on our list to fix.