Preliminary screening removed irrelevant apps (music/relaxation, happiness, inspirational cards, games, clocks, etc), apps not in English, and those that were not readily accessible. Mindfulness apps that were secular, explicated mindfulness practice, and also had guided mindfulness training were included. Apps that only gave reminders, timers, or guided meditation tracks were excluded, as were apps that cost more than $10 (on the grounds that they were unlikely to be purchased by a large number of users). While guided meditation tracks are a part of mindfulness training, that by itself cannot be justified as mindfulness training as they lack education about mindfulness.
The apps were rated and reviewed in iOS 7 with an iPhone 5s. Each app was tested by at least one author for a minimum of 30 minutes in a real-world setting. The authors were involved in the development of the MARS [24 (link)] and had undertaken mindfulness training. Two of the authors had delivered mindfulness training as part of their clinical psychology practice.