How do I send a text to a client?

Go to Texts, choose a conversation or click New Text / New Text Message, type your message and press Send (Cmd+Enter also sends). Use Attach file (MMS) to include an image or document.

You can also open a household and use its Texts tab.

Delivery status is shown per message: Queued, Sent, Delivered, Scheduled, Failed / Undelivered.