Question:
For custom SMS, what are the limits around characters that can be sent? Is there a hard stop (message gets cut off) vs being broken up into multiple texts?
Answer:
The sms character limit is 160, we can however send multiple messages in sequence, which is what will happen if you create an SMS longer than 160 characters.
From a usability perspective, I would definitely suggest keeping text messages shorter than 160 characters if possible. I know I would definitely be annoyed as a patient if I received a monster 3 sms message from my hospital!
Also if you are putting a URL in the message, I would recommend using bit.ly to shorten it.