Frysbe - Frysbe: Make global friends at random and the fling app comes up with features to send messages to strangers from every corner of the world to expand your social circle.
Postcrossing - A postcard exchange project that invites everyone to send and receive postcards from random places in the world. For free!
Yochat - Yochat app enables users to get to know about strangers from a large number of countries from around the world by video chatting with them.
swap-bot - Swap-bot is a online service that organizes group swaps and a community of creative individuals.
PenPal World - Connect with people all over the world
Random PenPals - Get a quarantine PenPal in 10 seconds