“…However, in another study that compared within group differences, only 20% of participants (10/51) aged between 50 and 94 years were reported to be capable of using a smartphone, as opposed to a larger smart tablet for data entry and active monitoring, and of these 10 people, only three considered the smaller device easy to use [28]. Lost or damaged device was a clear barrier to usability and participation, mentioned in four studies [8,13,15,26]. Further disruptions to response collection due to changes in service plans such that participants could no longer receive text messages [17] or excessive consumption of the smartphone batery [29] and was mentioned as a barrier to data entry completion in another study [10].…”