An exploratory study conducted at George Brown College in Toronto, Canada between 2007 and 2009 investigated language learning with mobile devices as an approach to augmenting ESP learning by taking learning outside the classroom into the real-world context. In common with findings at other community colleges, this study identified inadequate language proficiency, particularly in speaking and listening skills, as a major barrier for ESL college learners seeking employment, or employers hiring and retaining immigrants as employees (CIITE, 2004; Palalas, 2009). As a result of these findings, language support was designed to provide English language instruction going beyond the standard 52-hour course: a hybrid English for Accounting course encompassing in-class, online and mobile-assisted ESP instruction. This paper reports on the pilot study of the mobile component of this re-designed course, which represents the first stage of an on-going Design-Based Research (DBR) study. Discussion is also offered of a new learning theory which we have called Ecological Constructivism (Hoven, 2008; Jakobsdottir, McKeown & Hoven, 2010), devised to incorporate the multiple dimensions of Ecological Linguistics and Constructivism in the situated and context-embedded learning engendered by these new uses of mobile devices.