ConZentrate is an app that helps to improve your concentration by taking your mind to the Zenith of its limits. ConZentrate helps to improve your focus and the power of your mind. The original name for this technique is called as Trataka in Sanskrit. Trataka is a very well-known and famous technique for improving one's concentration and enhancing meditation practices of seekers of truth.
ConZentrate has both paid and free versions.
The best way to use the app is to focus on the moving ball and/or the sound of Om in the background. Let your breath relax as you are doing the above step. Once the mind is calmer then try focusing on the center Om or the dot.