Peeper has been discontinued. Similar apps include diaspora*, which is free and open source. Other options are Gab, VK, ZeroMe and Cato.social. In total there are seven Social Networks like Peeper for the web, Android, self-hosting, Mac and Windows.
Diaspora is a federated social networking service, designed to be a more privacy-aware alternative to Facebook . Share what you want, with whom you want.
United States
Gab Social is an open source and fully decentralized social network powered by the Gab Platform. It is the new social network of Gab.com. This change was made to further Gab's commitment to its users trust and privacy online.
United States
VK (originally VKontakte) is a largest social network service from Europe. Available in many languages and highly popular particularly among Russian-speaking users around the world, especially in Russia, Ukraine, Kazakhstan, Moldova, Belarus, and Israel.
Russia
Cato is an X (Twitter) alternative where you can post Meows, get Not So Anonymous Messages, connect with other Catos & grow your online social network.
Pen Pals by PenPal World - The Fastest and Most Secured Pen Pal Site in the World. PenPal World features over 2,000,000 pen pals from every country all over the world.
APSense is a business social network combining the best elements of business networking with the relationship building power of a social network.
United Kingdom