How to send Sms to many numbers using nexmo in ios?

I am new to Xcode, and I am developing iPhone app that need to send SMS.

In order to implement this, I used the JSON service of nexmo. The problem is only I can send SMS to my registered mobile number only and I cant sent to other numbers.It shows "Unroutable message - rejected" error.

Solution

I think now you are in test phase you can only send SMS to numbers added to your Permitted Destinations. After you top up your account this restriction vanishes. Now You can add up to 10 numbers of your choice Here