There is a comprehensive User Guide accessible from the home page. This explains all aspects of how to use the app.
You may see some tips appear when using the app. These tips highlight functionality available, for example, by using a long press on certain buttons.
Double-check that both sender and receiver have entered the same password.
Check that both devices are connected to the same WiFi network, and are not in Flight mode.
Some public and corporate networks do not support the features required for devices to find each other. The app uses mDNS service discovery, which in turn uses multicast UDP network traffic on port 5353. Check with your network administrator whether this type of traffic is blocked.
Email us at support@erayapps.com