A .NET library for accessing the Nexmo API. The docs for the Nexmo API are here.
First you need to sign up and get your API key and secret.
Then:
var response = new Nexmo(key, secret).Send(from, to, text);
Nexmo requires numbers in international format. If you have numbers in local format, you can use the International.Convert(number, [region])
methods to help with this.
US and Canadian numbers shouldn't need conversion.
Note: I haven't tested this on anything other than Australia, NZ and UK numbers, so please report an issue if it doesn't work for your region.