Wifi Manager is the best network toolkit app that you can use to monitor your connections on Wi-Fi. You can check all connections on Wi-Fi, make it private or public. To do this, you need to select any Wi-Fi network and select 'Turn Wifi On/Off' option. After this, click on 'Status' option and you will see all your devices connected to Wi-Fi networks. From there, you can choose the device and select the network that you want to monitor.

The best part of this app is that, you can turn on/off the Wifi network on your device and you don't need to connect to the internet to check if your device is connected or not. For all of you who do not know, you can use Wifi for free, you just need a wifi network and you are good to go.