According to a series of tweets by developer David L-R, he has discovered that a popular Instagram third-party app by the name of InstaAgent has actually been harvesting the usernames and passwords of its users, and has been using that information to log into the accounts of its users and post photos on their account without their consent.
For those unfamiliar with InstaAgent, basically the app claims to be able to show users who has viewed their Instagram account/photos. The app was downloaded more than half a million times. Thankfully Apple has since caught onto the app and has removed it from the iTunes App Store. However the question here is how did it even make it past the review process in the first place?
Apple has yet to comment on the app and how it made it past their review process, but like we said if you ever needed a reminder that unofficial third-party apps and services might not be the best idea, this could be it. In the meantime if you have downloaded the app, perhaps you should think about changing your Instagram username and password just to be safe.