Headspace is one of the most popular meditation apps. Using simple videos and exercises, it teaches you to concentrate, breathe, and meditate to relieve all kinds of problems related to everyday stress, including insomnia, anxiety, lack of concentration, and more.
The app offers you the first ten sessions for free in the form of a training plan, so you can familiarize yourself with the mindfulness. Subsequently, if you wish to continue using it you must pay. Its other disadvantage is that the meditation guides are currently only available in English, although the voice speaks extremely clearly and understandably.