  In this article we address the question of how to measure the size and
characteristics of the platform economy. We propose a~different, to sample
surveys, approach based on smartphone data, which are passively collected
through programmatic systems as part of online marketing. In particular, in our
study we focus on two types of services: food delivery (Bolt Courier, Takeaway,
Glover, Wolt and transport services (Bolt Driver, Free Now, iTaxi and Uber).
Our results show that the platform economy in Poland is growing. In particular,
with respect to food delivery and transportation services performed by means of
applications, we observed a growing trend between January 2018 and December
2020. Taking into account the demographic structure of apps users, our results
confirm findings from past studies: the majority of platform workers are young
men but the age structure of app users is different for each of the two
categories of services. Another surprising finding is that foreigners do not
account for the majority of gig workers in Poland. When the number of platform
workers is compared with corresponding working populations, the estimated share
of active app users accounts for about 0.5-2% of working populations in 9
largest Polish cities.
