The FDA lets the entire NIH National Center for Complementary and Alternative Medicine (NCCAM) get $128 million per year without giggling but this iPhone app is apparently a concern. How would they feel jurisdiction over an iPhone? The chemical strips which determine the levels of elements in urine become, when used by uChek, part of an "automated strip reader" and therefore a medical testing system that requires its approval. Even though the strips are meant to be read by eyes.
Actually, this is great marketing for them; 'FDA approved medical testing system' - heck, they can even get insurance to pay for it that way.
iPhone urine analysis app may require FDA approval, says agency By Nathan Olivarez-Giles, The Verge