Apps can provide hours of entertainment, keep you organized, and help you learn something new. Indeed, apps can be helpful, as long as they provide accurate information. But if you’re trying to analyze a serious medical condition with an app — like whether that mole on your back might be a sign of melanoma — talk with your doctor or another reliable medical professional first. As recent FTC cases show, some health apps make claims they can’t back up.

The FTC recently brought cases against marketers who advertised that their apps — Mole Detective and Mel App — could detect melanoma, even in the early stages, through analyzing a photo of a mole. The problem, the FTC alleged, was that these marketers didn’t have scientific evidence to back up their claims.

Based on photos and information provided by consumers, the apps were supposed to be able to calculate the mole’s risk of being melanoma as low, medium, or high. But if these apps incorrectly said a mole had a low risk of melanoma, when in fact it was cancerous — then what? It might cause someone to delay seeing a doctor. The reverse also could be alarming — if the app detected melanoma, but it later turned out you didn’t have it. Without proper scientific proof, there’s no way to know if the apps’ conclusions were accurate.

The bottom line? It’s fine to look online or use an app to learn more about various health issues, but it’s best not to rely on an app to diagnose or detect a serious medical condition.