While Spocket does not send your customers any messages directly about their orders, your customers can be automatically informed through Shopify.
Here is how you can enable shipped order notifications:
From your Shopify account, click Settings, then select Checkout
Scroll down to Customer Contact section, and then check To receive shipping updates so that customers can choose to add a phone number or email to receive shipping updates after they complete their order
Click Save to apply the changes
You can customize these notifications by going to Shopify Settings and selecting Notifications.