  The difficulty of large scale monitoring of app markets affects our
understanding of their dynamics. This is particularly true for dimensions such
as app update frequency, control and pricing, the impact of developer actions
on app popularity, as well as coveted membership in top app lists. In this
paper we perform a detailed temporal analysis on two datasets we have collected
from the Google Play Store, one consisting of 160,000 apps and the other of
87,223 newly released apps. We have monitored and collected data about these
apps over more than 6 months. Our results show that a high number of these apps
have not been updated over the monitoring interval. Moreover, these apps are
controlled by a few developers that dominate the total number of app downloads.
We observe that infrequently updated apps significantly impact the median app
price. However, a changing app price does not correlate with the download
count. Furthermore, we show that apps that attain higher ranks have better
stability in top app lists. We show that app market analytics can help detect
emerging threat vectors, and identify search rank fraud and even malware.
Further, we discuss the research implications of app market analytics on
improving developer and user experiences.
