  Translation apps and devices are often presented in the context of providing
assistance while traveling abroad. However, the spectrum of needs for
cross-language communication is much wider. To investigate these needs, we
conducted three studies with populations spanning socioeconomic status and
geographic regions: (1) United States-based travelers, (2) migrant workers in
India, and (3) immigrant populations in the United States. We compare frequent
travelers' perception and actual translation needs with those of the two
migrant communities. The latter two, with low language proficiency, have the
greatest translation needs to navigate their daily lives. However, current
mobile translation apps do not meet these needs. Our findings provide new
insights on the usage practices and limitations of mobile translation tools.
Finally, we propose design implications to help apps better serve these unmet
needs.
