Hydro Calculations is a free, Android-based mobile application developed by Toys of Black Box. It is a comprehensive hydrostatics and hydrodynamics solver and calculator, with features that cater to the needs of hydraulic students.

The app is divided into two main categories: hydrostatics and hydrodynamics. The hydrostatics category consists of hydrostatic pressure, Archimedes principle, and hydraulic press. On the other hand, the hydrodynamics category includes Flow rate, Bernoulli's principle, Continuity equation, Torricelli's law, and calculation of flow rate in an open channel.

What sets Hydro Calculations apart is the inclusion of schematic pictures and formulae on every page. This feature makes it easier for users to understand the calculations and the concepts behind them. The app is user-friendly, accessible, and a must-have for anyone studying hydraulics.