Mobile technologies and platforms that facilitate communication across different languages are increasingly relevant in a world characterised by the global flows of diverse populations and disparate digital environments. This qualitative study explores communication between native and non-native speakers of Korean, mediated through mobile instant messaging in the sophisticated digital environment of South Korea. This article reports on two studies that examined the experiences of English-speaking language instructors (Study 1) and international students (Study 2) in a private university situated in South Korea during 2012 and 2015, respectively. This is done by focusing on face-to-face and screen-to-screen communication, and the co-dependencies arising between language instructors and international students. Between 2012 and 2015, large upgrades in the local digital environment saw the emergence of ubiquitous low cost or free high-speed Wi-Fi coverage and a near universal national adoption of a local mobile instant messaging service. The participants in Study 2 were widely found to be digitally literate and demonstrated an acuity with mobile instant messaging. They developed creative solutions for communication and language learning by blending sociolinguistic and linguistic competencies within mobile instant messaging chat rooms. This article highlights the changes that have occurred between 2012 and 2015 and demonstrates the need for further research into how mobile instant messaging services support communication between people from different language and culture backgrounds, particularly for people without access to formal language instruction.