"I guess what we have learned is that withholding information about drugs is actually causing harm, because people will take drugs nevertheless," said 35-year-old Philipp Kreicarek, creator of KnowDrugs, an app that provides information about the latest drug-testing results, psychoactive substances and tips on safer use.

Kreicarek studied social work at university and worked as a drugs counselor, focusing on harm reduction in clubs and at parties on the side. At that time, club and festivalgoers received information about potentially dangerous pills at information stands or by checking specific websites.

He realized that many people were simply not aware of certain risks. For example, party drugs such as ecstasy pills have now become more highly concentrated. Sometimes, they are likely to contain up to three or four doses in one pill, or even a different substance entirely. Kreicarek thought that a better way to reach people would be via an app.

"I think those kinds of overdoses can be prevented with honest information," he told DW. "In general, I think knowledge about psychoactive substances allows people to make informed decisions and follow safer use practices which will help reduce harm."

KnowDrugs is free to download, and users aren't required to submit any personal data. It currently has about 80,000 monthly active users, 87% of whom are based in Germany, mostly in Berlin. It's also popular in Budapest, Warsaw, London and Paris.

Kreicarek works closely with addiction counseling centers and the new Drug-Checking Berlin service, which notify him if there is a warning about a specific drug or batch of........

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