We present an exploratory study examining why people in a relationship use Tinder and whether they score higher on certain (dark) personality traits compared to single users and non-users in a committed relationship. Our results indicate that non-single Tinder users differ significantly on nine Tinder motives from single Tinder users. Moreover, non-single Tinder users generally report a higher number of romantic relationships, French kisses, one night stands, and casual sexual relationships with other Tinder users compared to single Tinder users. In terms of (dark) personality traits, non-single Tinder users score significantly lower on Agreeableness and Conscientiousness, and significantly higher on Neuroticism and Psychopathy compared to non-users in a committed relationship. For non-single Tinder users, lower scores on Agreeableness and Neuroticism and higher scores on Psychopathy and Machiavellianism are significantly correlated with the sexual Tinder motive. Additionally, Narcissism and Machiavellianism were positively associated with using Tinder for an ego-boost. Non-single users who reported to have had offline encounters with other Tinder users reported higher scores on Extraversion and Openness to Experience compared to non-single users who never had an offline encounter.