"Just by sending messages, metadata is delivered to WhatsApp every time," said Kelber, adding that it could be assumed that these data snippets were then forwarded directly to Facebook, WhatsApp's parent concern.
"These contribute, even if only as a small piece of the mosaic, to the increased storage of personal profiles," he wrote, referring to IP addresses and locations.WhatsApp, cited in Handelblatt's Monday edition, rebutted Kelber's warning, saying the messaging service did not forward user data to Facebook — for example, to enable more accurately the distribution of online advertising.
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DW investigation finds private Whatsapp groups can still be found online
"WhatsApp cannot read messages because they are encrypted throughout by default," said its spokesman.
Only the people who sent messages to each other could read them — but not WhatsApp, Facebook or anyone else, asserted the commercial service.
In recent weeks, Kelber has also entered debate in Germany about plans to create viral tracing and vaccination apps, warning that a person's health data must be especially protected in the online realm.
ipj/rc (AFP, KNA)