Get started with Nexmo with tutorials that will walk you through building a variety of practical applications
By asking your customer to provide a phone number — and then validating the legitimacy of that number — you minimize fraud and ensure that you can easily contact that customer in the future.
Use the Number Insight and Developer API from Ruby code to validate, sanitize and determine the cost to call or message a number.
While it would be easy to confirm a phone number with Nexmo Verify every time a user provides you with their number this is hardly always necessary. By combining Nexmo Verify with Nexmo Number Insight, and applying your own fraud scoring logic, it is easy to build your own fraud detection system.