QBUUser *user = [QBUUser user];
user.login = @"garry";
user.password = @"garry5santos";

[QBRequest signUp:user successBlock:^(QBResponse *response, QBUUser *user) {
    // Success, do something
} errorBlock:^(QBResponse *response) {
    // error handling
    NSLog(@"error: %@", response.error);
}];

QBUUser *currentUser = [QBUUser user];
currentUser.ID = 2569; // your current user's ID
currentUser.password = @"garrySant88"; // your current user's password

[[QBChat instance] connectWithUser:user completion:^(NSError * _Nullable error) {
    NSLog(@"Error: %@", error);
}];