Just launched a new Coinwink feature that allows you to use SMS alerts for free.
You can start using this new feature here:
https://coinwink.com/#smsYou will need to provide your own SMS sending API that you can get for free with 2$ credit from Plivo or Nexmo.
Please let me know if it works great or maybe something is missing or can be better. Your feedback is very valuable.
P.S. You can still use email alerts as before, with or without the account, but with account it is more comfortable.
https://coinwink.com/#smsGood luck!
Have you heard of Twilio? They are a good API provider for SMS and mms messages, as well as other forms of communication. I think it's like $3,000 for a code and then a few cents per message or something. Could be worth it if you have a lot of users who want this service.