Quantum Well Free app calculates bound state energy levels of a quantum particle under the influence of a potential well. The app provides you up to four lowest energy levels, if available. Depending on the input parameters you might not have four levels or you could also have more. In general, people are mainly interested in the ground state energy within the quantum well, and possibly the first excited state. The quantum well energy levels are utilized, for example, in designing light emitting/absorbing nano structures, and they are related to considering energies of electron-hole pairs, i.e., excitons. Due to this mobile application these non-analytical energy levels are now easily obtainable.

In the app there are three input parameters (Width, Depth, and Mass):
- Width: Describes the width of the potential well, and should be given in units of Ångström (Å). For example, 10 Ångströms is equal to 1 nanometer.
- Depth: Describes the depth/strength of the potential well, and should be given in units of electron Volts (eV).
- Mass: Refers to the mass of the quantum particle in the potential well. The mass should be given as a multiple of the electron mass. For example, an electron in the well would have mass 1. Depending on the nanostructures, the conduction band electron masses are either slightly larger or smaller than one. And the same applies for the hole masses at the valence band.