Microsoft soon will release wave 1 2021, enabling users to design and send SMS from Dynamics 365 Marketing out from Customer Journeys. 
Before the new release, SMS was possible using third party ISV and required to open mobile number accounts to send those SMSs.
Contact Preference
At the moment there is no SMS as one of the options to allow or disallow receiving SMS under the contact preference.
It is expected that Microsoft will add SMS to collect contacts consent.
Subscription List
A new subscription list can be created for the new SMS channel will to comply with the General Data Protection Regulation GDPR compliance. Having a specific subscription list will allow Dynamics 365 Marketing contacts to opt-in and opt-out of SMSs or other channels such as emails.
Push Notification to mobiles
A new feature was introduced in wave 1 2021 to push notification from model-driven apps, read more
According to Microsoft’s announcement regarding the new Dynamics 365 Marketing wave 1 2021, users will be able to push notifications to ease reach to contacts and clients.
Design and Send SMS from Dynamics 365 Marketing
Once the new feature is out, we will write a detailed post explaining how to create SMS and include SMSs in Customer Journey.
