Introduction Currently, many sunscreen mobile apps are available for use. However, little is known about their characteristics. We aimed to describe the available sunscreen mobile apps for Android and iOS. Material and methods An observational descriptive study was conducted. We searched in App Store and Google Play Store using specific terms in Spanish and English, and collected the mobile apps that aimed to improve sunscreen use. We extracted general characteristics from all of these apps, and specific characteristics from free apps. Results We found 134 apps that aimed to improve sunscreen use, of which 88 (65.7%) were available only in English, 92 (68.7%) were free of charge, and 53 (39.6%) were updated in 2015 or 2016. We evaluated specific sun protection features of free apps: 5 (5.4%) included videos or animations, 2 (2.2%) included games, 28 (30.4%) had institutional certification, 64 (69.6%) indicated the UV index according to user current location, and 16 (17.4%) informed about the appropriate sunscreen use. Discussion The majority of dermatology-related apps were available for free maybe because of their high demand among users. Moreover, they were downloaded mostly more than 1000 times perhaps due to a major concern about the harmful consequences of the UV-rays on health among people. Most of the mobile apps evaluated had no institutional certification that is important for guarantee an appropriate display of information on the app. Conclusions Most of sunscreen mobile apps were available free of charge and were recently updated. However, few free apps have institutional certification, interactive features, and sunscreen use information; which may limit their impact.