This article reports on research investigating the relationship between text messaging and academic literacy among Spanish-dominant emergent bilingual young adults in New York City (acquiring English). Through assessments of academic language and analysis of a corpus of 44,597 text messages, this study found that emergent bilinguals who send more messages in English and choose English for the settings on their mobile phones tend to have higher academic English skills. This study also found that the English messages they send are lexically less dense than the Spanish messages, illustrating that students use a narrower vocabulary when texting in their second language. This finding is explored in light of previous research that has found that using social media in the target language can help students develop fluency and intercultural competence skills, but not always vocabulary. The results are discussed in terms of the tendency for texters to text monolingually and other affordances and constraints of smart phone use in digitally supporting second language acquisition.