Mobile health apps can contribute to increased quality of individual oral hygiene behaviors. This study provides an overview and an evaluation of quality of oral-hygiene-related mobile apps currently available in Google Play Store and the French Apple App. A shortlist of nine apps was assessed by 10 oral health professionals using the Mobile App Rating Scale. Intraclass correlation was used to evaluate interrater agreement. Best quality scores were obtained by Oral-B (3.4 ± 0.97), Colgate Connect (3.20 ± 0.63), and Preventeeth (3.10 ± 1.1) and worst ones by Mimizaur se brosse les dents (1.80 ± 0.79) and Kolibree (2.30 ± 0.82). The subjective quality scores ranged from 2.62 ± 0.61 (Oral-B) to 1.5 ± 0.61 (MSD). Specificity of the content ranged from 3.46 ± 0.84 (Preventeeth) to 1.78 ± 0.47 (Mimizaur se brosse les dents). Thus, even if oral health professionals positively evaluated the quality of oral-hygiene-related mobile apps, they are less assertive concerning their impact on the user’s knowledge, attitudes, and intentions to change, as well as the likelihood of actual change in the oral hygiene behavior. Further investigations are needed to assess whether information from these apps is consistent with oral hygiene recommendations and to determine the long-term impacts of these apps.