I've got a short paper in ICTD 2013. The title is "Mobiles and Migration: Global Data on Immigrant Population and Mobile Subscriptions" and the abstract is below. You can also download the data, R code, draft paper and the bubble chart I used on my poster.
Expanding on recent findings on mobile phones as enablers of domestic labor mobility, this paper considers the relationship between immigrant population and mobile cellular subscriptions. Regression analysis shows that the immigrant proportion of a country's population significantly predicts mobile cellular subscriptions per 100 people, controlling for GDP (p < .01). Further, the model explains 24% of the variance in the dependent variable, compared to only 15% for GDP alone.