Google has announced that it will be discontinuing its free SMS alert service for Google Calendar from June 27th.
The company cites the growth in smartphone usage and improvements in technology as reasons for killing off the service:
Starting on 27 June 2015, SMS notifications from Google Calendar will no longer be sent. SMS notifications were launched before smartphones were available. Now, in a world with smartphones and notifications, you can get a richer, more reliable experience on your mobile device, even offline.
To receive notifications on your smartphone, either configure the calendar app that came with your device or install Google Calendar for Android or iPhone. For more information on how to configure notification defaults, have a look in the Help Centre.
Please note: Please note: This change will not affect Google Drive for Work, Google Apps for Work (paid edition), Education and Government customers.