Here's an unpleasant surprise for many iPhone and Android users: some apps continue to track you -- after you uninstall them! The ball is now in Apple and Google's court to stop this behavior.
Security expert Robert Siciliano says it's a definite threat to privacy.
"This is very disturbing; the fact that you uninstall software and there are remnants of that software still there that are tracking you is a relatively new development."
Siciliano says don't install apps on a whim.
"I evaluate every application as to why I need it -- what the pros and cons are -- and I look at the terms of service and terms of conditions."
Siciliano says there's no reason to panic; if you're really troubled by this you can always reinstall your phone's operating system.
"I wouldn't say 'worry about it' that's just quality of life stuff, but I definitely would be aware and alert of it and you can always reinstall your OS."
Siciliano says Apple and Google consider this a breach of their app developer policies, but we'll have to wait and see what they do about it.