Indeed, in the Alabama case last month, police arrested a teen after they tracked a shooting threat made on the service to his phone.
And experts say it is unlikely that users would have a legal case to sue the app developer, claiming that he failed to uphold the promise of anonymity. "Most promises of anonymity have a loophole indicating that access may be provided to law enforcement or to appropriate authorities as required by law," Herold said.
She said Big Data analytics, network logging and geolocation defaults within mobile devices, "all provide means for linking online activities with specific individuals in more situations than ever before. Anything posted to social media will never be truly anonymous."
Cleary agreed. "You can never guarantee anonymity, and I'm sure that the terms and conditions for use do not guarantee it," he said.
And on the flip side, he said the policy banning an app's use by those younger than 17 won't result in any punitive action against an "under-age" user. "It's designed to protect the company from liability," he said.
Payton said users should not confuse privacy with anonymity, given the "digital tracks" that are left with every post. "Your phone or tablet have unique device IDs," she said. "Your profile is often tied to an email account. Even the geolocation of where you check in might be collected. All of these data points can strip away your anonymity."
She recommended what most teens would never take the time to do -- "read the policy privacy statement of Yik Yak and other apps very thoroughly. You might be giving away more about yourself then you think."
All of which brings it back to the very non-tech reality that communication and supervision by parents and other adults offers the best hope of curbing the abuse of apps like these.
"My 10-year-old is part of a virtual social network with all his classmates using Viber," Cleary said. "There could easily be bullying with this app also, so it goes back to education of kids with phones."
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