Can I send SMS from a custom module ?

Yes, you can send a SMS from a custom module.

You need to have Phone Calls module enabled in your instance.

Steps to send SMS from a custom module

1. Click Customize button in the top right
2. Select Fields & Layouts
3. Add New Field
4. Create Custom Field SMS Text, select field type Phone
5. Create Custom Field Send SMS, select field type checkbox
6. Add a New Workflow
7. Add Workflow name, target module
8. Select Workflow Trigger Only first time conditions are met
9. Add Condition Send SMS is enabled
10. Add Action SMS Task
11. Save Workflow

Now, you can send SMS directly from a custom module.