diff --git a/piwik/README.md b/piwik/README.md
index 1863253..f65a070 100644
--- a/piwik/README.md
+++ b/piwik/README.md
@@ -1,10 +1,7 @@
 # Piwik Plugin
 
-The Piwik plugin allows integrating Indico with a Piwik instance to gather
-statistics about the users accessing Indico or specific Indico events.
-
-Please note that the plugin has not been tested with Piwik's successor,
-Matomo, so we do not know whether it is compatible with it or not.
+The Piwik plugin allows integrating Indico with a Piwik or Matomo instance to
+gather statistics about the users accessing Indico or specific Indico events.
 
 ## Changelog
 
diff --git a/piwik/indico_piwik/queries/graphs.py b/piwik/indico_piwik/queries/graphs.py
index 8fecf6d..0ce5a4c 100644
--- a/piwik/indico_piwik/queries/graphs.py
+++ b/piwik/indico_piwik/queries/graphs.py
@@ -46,5 +46,5 @@ class PiwikQueryReportEventGraphCountries(PiwikQueryReportEventGraphBase):
 
 class PiwikQueryReportEventGraphDevices(PiwikQueryReportEventGraphBase):
     def call(self, **query_params):
-        return super().call(apiModule='UserSettings', apiAction='getOS', period='range', width=320, height=260,
-                            graphType='horizontalBar', **query_params)
+        return super().call(apiModule='DevicesDetection', apiAction='getOsVersions', period='range', width=320,
+                            height=260, graphType='horizontalBar', **query_params)