The analytics team is happy to announce that the Unique Devices data is now
available to be queried programmatically via an API.
This means that getting the daily number of unique devices  for English
Wikipedia for the month of February 2016, for all sites (desktop and
mobile) is as easy as launching this query:
You can get started by taking a look at our docs:
If you are not familiar with the Unique Devices data the main thing you
need to know is that
is a good proxy metric to measure Unique Users, more info below.
Since 2009, the Wikimedia Foundation used comScore to report data about
unique web visitors. In January 2016, however, we decided to stop
reporting comScore numbers  because of certain limitations in the
methodology, these limitations translated into misreported mobile usage. We
are now ready to replace comscore numbers with the Unique Devices Dataset .
While unique devices does not equal unique visitors, it is a good proxy for
that metric, meaning that a major increase in the number of unique devices
is likely to come from an increase in distinct users. We understand that
counting uniques raises fairly big privacy concerns and we use a very
private conscious way to count unique devices, it does not include any
cookie by which your browser history can be tracked .