Router Admin Page is a handy app that will allow you to view and manage your connected router/modem. It doesn't require you to memorize the IP address as it will do that for you.

It allows you to view all your connected devices and manage your router settings like adding and removing users, configuring the router's IP address, Wifi password, Wifi settings, etc.

This application is very easy to use. Just install it on your device and launch it. You will be guided through the setup wizard. After you finish setting up the app, you can simply save everything you configured.