Hundreds of millions of language learners around the globe study a second language with popular apps such as Duolingo, Rosetta Stone, Busuu, and Babbel. This study examined the effectiveness of one app, Babbel, for developing both receptive linguistic knowledge of vocabulary and grammar, as well as oral communicative ability in Spanish as a second language. Fifty-four English speakers not enrolled in Spanish classes studied Spanish on Babbel over the course of 12 weeks, with a goal of studying roughly 10 min per day. Participants completed pretests and posttests, and provided data on their motivation to learn Spanish and use Babbel. Results showed that learners were able to develop grammar and vocabulary knowledge as well as oral communicative ability. The amount of Babbel study time was the strongest predictor for all three measures, with motivation to learn Spanish also significantly predicting growth in oral communicative ability.