It is called Remote Pro or simply remote control for Mac and costs otherwise about ten euros. Of the many good remote control apps for the Mac, the app is one of the most complete and at the same time tidiest, with a well thought-out structure and a beautiful design.
In the full version you get all functions for free and can start programs, remote control the specific functions, create your own remote control layouts and even mirror the current image from your Mac to your iPhone or iPad.
When rating, please have in mind that the developer is an independent indie developer. So be a bit more generous in your rating and try to solve a possible problem in a nice way beforehand. However, we rather believe that you will be very enthusiastic about the app.