How SMS notifications are sent? Is there any fee associated with sending sms notifications, or is it free? I don’t see, any information in the FAQ.
thats nice, but how did you do that? I’m in Poland/Europe and I can recive free sms every time i switch off my arduino - how cool is that? 6months ago i did a project with gsm shield and sim card, Now I can achieve this using only ethernet shield? how do you do it? what system allows you to sending free messages?
They are probably either eating the cost and sending via standard SMS (probably Twilio) or sending the SMS using your carrier’s email-to-SMS gateway.