Why a Lovable app can look fine and still break on a phone

You built the app on a wide screen. The builder preview is wide too. A visitor on a phone gets a different page.

A common break is sideways scroll. A box, an image, or a nav bar is wider than 390 pixels. The person has to drag left and right to read a sentence. They often leave.

Another break is a button that is too small to tap, or a button that sits under a sticky bar. It looks tappable. A thumb misses it.

Before you share the link, open the app at a phone width. Or run a check that does that for you and shows the screen where it failed.

TestMyLaunch walks the first page at 390 pixels wide and at a desktop size. The free check lists what it finds. The full report adds a screenshot and a prompt you can paste back into Lovable, Bolt, v0, Replit, or Cursor.