This video shows how to build and test an Ionic SMS app using Nexmo API. The video tutorial first shows how to create a backend to invoke Nexmo API. Then the Ionic app is created which uses the backend. The app is then tested in the browser and on the device using the Appery.io Tester app. The video also shows how to build a binary file for Android and iOS.
Also, check out how to create an app backend with API Express and Nexmo SMS API.