Toca Boca is taking things from finger to toe. The Swedish mobile developer, which has recently surpassed the 50 million download mark for its suite of customizable kids apps, is collaborating with manufacturer Happy Socks on four exclusive designs.

Starting this month, fellow Sweden-based company Happy Socks will sell two-packs of socks that feature characters from the Toca Kitchen Monsters app. Nebula and Gomez will adorn one pair of socks, while the Toca Boca logo colors will brand the other pair in the pack.

This marks the first children’s collaboration for Happy Socks, whose products are sold in more than 70 countries. It also marks an inaugural move for Toca Boca into the physical product space, an almost requisite one that’s being increasingly made by competitors like Finland’s Rovio and Cyprus-based Outfit7.