Millions of smartphones are vulnerable to attack over your Wi-Fi connection. An attacker can, and will, take control of your Android or Apple device.
Attackers with high skills can also deploy malicious code to take full control over your device and install malicious apps like banking Trojans, ransomware, and adware without your knowledge.
Both Google and Apple have released updates.
Google update here:
https://source.android.com/security/bulletin/2017-04-01
Apple update here:
https://support.apple.com/en-us/HT204204
More information here:
http://thehackernews.com/2017/04/broadcom-wifi-hack.html
Please forward this on to your family and friends who have smartphones.