Yes - your SuperPhone™ number(s) can call and text internationally.
SuperPhone™ is built on Twilio - the powerful Cloud Communications Platform that connects Uber to their customers and you to your global network of contacts.
Selective Carrier Re-routing
In some countries (France is an example) your message will be re-routed by the mobile carrier to a generic short code before being delivered. In those cases, your conversation will be split between two numbers: your SuperPhone™ number and the carrier specified number for Twilio messages.