The mobile applications (apps) industry has exhibited rapid entry and growth in the midst of a recession. Using unique data from the iPhone application ecosystem, we examine how the development of "killer apps" (apps appearing in the top grossing rank) varies by market and app characteristics....

Social interactions are considered pivotal to urban agglomeration forces. This study employs a unique dataset on mobile phone calls to examine how social interactions differ across cities and peripheral areas. We first show that geographical distance is highly detrimental to interpersonal...

Social interactions are considered pivotal to agglomeration economies. We explore a unique dataset on mobile phone calls to examine how distance and population density shape the structure of social interactions. Exploiting an exogenous change in travel times, we show that distance is highly...