cloudcode.js

var twilio = require('twilio');

Parse.Cloud.define('capability', function(request, response) {
    var cap = new twilio.Capability();
    cap.allowClientIncoming('bondjamesbond');
    response.success(cap.generate());
});

SomeFile.m

[PFCloud callFunctionInBackground:@"capability"
                   withParameters:nil
                            block:^(NSString *token, NSError *error) {
    TCDevice *device = [TCDevice initWithTokenOrWhateverIForget:token];
}];