Check out Gofer messaging for sending short radio messages to your pals:
Gofer is a secure text messenger offering complete message privacy and security. Gofer messages are short radio messages. They don't need internet connection to be transmitted. Upon reaching your friend's phone, it dissapears after the first read. It can also work in stealth mode by hiding the sender details and contact information in the alerts.
https://play.google.com/store/apps/details?id=org.gofer.app
Gofer is a secure text messenger offering complete message privacy and security. Gofer messages are short radio messages. They don't need internet connection to be transmitted. Upon reaching your friend's phone, it dissapears after the first read. It can also work in stealth mode by hiding the sender details and contact information in the alerts.
https://play.google.com/store/apps/details?id=org.gofer.app