Is it possible to send SMS from a mobile phone or only from the portal?
Yes, you can send SMS to the Things Mobile SIM card number directly from your mobile phone by prefixing the number with either the "+" sign or "00". Make sure that the local number is enabled to send and receive international SMS. If an SMS sent from the local number is not delivered, check with your provider for the SMS routing for undelivered messages.
Alternatively, you can also send SMS from the IoT portal. Response SMS will be visible in the VIEW SMS section.