In case there is a problem with the Wi-Fi connection, here are a few things you can do to check it:

For 4 and 5, you may need to check with your Internet Services Provider

1) Reset your device and restart the installation;
2) Check the distance between your screen and your router;
3) Avoid interference with other Wi-Fi devices you may have;
4) Adjust the power of your firewalls, at the level of your at a router level;
5) Change the encryption of your Wi-Fi key to WPA-PSK or to WPA2-PSK;
6) Activate notifications, and mobile data on your smartphone;

If nothing works, you can, alternatively, switch to a cable-based installation (RJ45);

Note: Make sure you're running compatible versions of your system on your smartphone (iOS: 7.0 and above / Android: 2.2 and above)