IP Calculator is a free utility application designed to help Network Engineers, IT Professionals, Network Administrators, and Students with calculating and manipulating IP address-related tasks. Developed by Technosoft Labs, this app has an adaptive and sleek design for a better user experience.

The app's essential features include determining the IPv4 address class, available subnets, hosts per subnet, network address of the given IP address, first and last host of the given IP address, broadcast address of the given IP address, binary notation for IPv4 address and subnet mask, subnetting and supernetting table for getting various IPv4 address range, and more. With its real-time calculation feature, each field changes dynamically.

Moreover, IP Calculator tells whether the given IP address is private, public, loopback, APIPA, etc. The subnet mask auto-adjusts based on the given IP address, and there's a slider for changing the subnet mask easily at runtime. The app also comes with a bug tracker for tracking bugs if any. It supports both phone and tablet versions of Android devices.

Overall, IP Calculator is a must-have tool for network professionals who need quick access to IP address-related calculations. While the app is free, it would be great if the developer could add more features to make it even more useful.