Developed by Lithuania-based firm Deep Sea Marketing, the app "infects" four nearest friends who also have the app installed with the new content.
Receivers can either decide to continue disseminating the message by swiping upward - sending the post to additional four users - or stop it from spreading by swiping downward.
There is also an option to comment on posts, Newsweek reported. Apart from the original post and any comment, those who contribute to a post's spread are not made public.
"We now want to take Plague off-the-grid like FireChat - an app that lets users communicate anonymously in the absence of Wi-Fi or cellphone service," Plague's co-creator Ilya Zudin was quoted as saying on Gigaom.com.