Tip: If you are running your own PHP "provider" server, don't worry about converting it to a string on the device. Just send the token as binary data to your registration endpoint and convert it to a string using:$tokenString = bin2hex($tokenData);Store it in your database as a string. This makes sense because, later when you want to send a push notification, you will be using the bin2hex string version in the url anyway.$pushURL = "https://api.development.push.apple.com/3/device/$tokenString";