In this paper, we overview the design of tablet apps we designed and built to teach literacy to adults, and present the results and conclusions derived from experiments performed with target users. Low adult literacy is a significant problem with a high economic cost both for the individuals and for society. Programs created to address low adult literacy face access and engagement barriers that tablet software may be able to help overcome. We designed three tablet apps, using two contrasting approaches of incorporating game-design elements to engage the users. We tested the apps with participants from the Brant Skills Centre, a non-profit organization that offers adult literacy programs in Brantford, Ontario. Though participants were divided on whether they preferred the apps to more traditional instruction, most participants preferred using the apps in addition to more traditional instruction. Based on this we conclude that gamification and serious game design approaches were effective at increasing learner engagement, and we propose a direction for future research.