Researchers at Oxford University told the Financial Times newspaper that almost 90 percent of free apps on the Google Play store share data with Alphabet, which is Google's parent company.
But Google has already hit back at the research, insisting that it has clear policies in place that detail how data should be handled.
The world-famous tech firm said, too, that the study had mischaracterised some "ordinary functions" of apps.
Google added: "If an app violates our policies, we take action."
This comes shortly after Google announced that smartphone manufacturers will soon no longer have free access to apps on Android.
The licensing fee charge was introduced after Google was handed a $.4.9 billion fine by the European Commission, which accused the tech giant of anti-trust violations.
Android phones and tablets have, until now, all been pre-installed with Google's search engine, as well as the Chrome browser.
But that scenario has recently been considered to be illegal by the European Commission.
As a result, from October 29, all new Android devices in Europe will be brought into line with the licensing charges.