WiFi Priority Manager

WiFi Priority Manager is an Android app which allows a user to change the priority of configured WiFi networks

Most of Android devices don't let the user to take control on the priority of the configured WiFi networks.
With WiFi Priority Manager you can do that simply by dragging and dropping your configured WiFi network in your preferred order.

Get WiFi Priority Manager on Google Play Store

WiFi Band

WiFi Band is an Android app that notifies the user about the radio bandwidth and the SSID of the connected WiFi network.

Even if the app is still in beta version, you can give it a try.

You can find more details in the WiFi Band page of the blog