Seems like the only way to add friends is via your email you registered for your account. Mine is mkioshi at me dot com (not putting it at a friendlier format because ya know, robot spammers and stuff)
you can add: [email protected] We hope it's going to be a bit of challenge. More tips here: http://thegamebakers.com/combo-crew-tips-from-the-developer.html See you soon in the game!