• Dont use WEP security (declared deprecated in 2004 because of its security limitations) use WPA or WPA2 (WPA3 comming soon).
• Try not to use a wireless extender as the reliability and retransmission of packets degrades the connection.
• The strength of the security is as strong as the password is.
• There is nothing wrong with 2.4ghz other than its slower than 5.8ghz however the 2.4 frequency is less line of sight and more reliable traversing obstacles. If you are close to the access point or have direct line of sight then 5.8 is great.
• If you want privacy hide your SSID and use MAC filtering with encryption. MAC filtering is done on the AP and only allows the devices whos MAC addresses you have added to the whitelist.
• If you are not getting great performance on your Wi-Fi network then check that the frequency your access point is running on is not the same as your neighbours or another device. This is interferance and easily reolved.
• REMEMBER: there is no better connection that a physical connection.

Public hotspots are all location traced and visible all over the globe. Bandwidth required for casual browsing: 0.5 - 5Mbps. For high definition streaming 5Mbps and for 4K streaming 25Mbps. Netflix recomends a 25Mbps Internet connection per session. If you want four sessions then 100Mbps is recommended (in my experience is absolutely overkill 10Mbps connection is good for two people). For a good all round wifi application and testing tool use: Netspot For more information: see there blog.