Google has warned Android developers to give users better warnings about their apps' data collection behaviours, or it will flag their failings.

Last Friday, the company announced revisions to Safe Browsing rules and "expanded enforcement of Google's Unwanted Software Policy".

If developers don't comply within 60 days, Google said, it will warn users via Google Play Protect “or on webpages that lead to these apps”.

“Google Safe Browsing will show warnings on apps and on websites leading to apps that collect a user’s personal data without their consent”, the announcement said.

If an app handles either personal data (phone number, e-mail) or device data (such as IMEI number), developers will have to both prompt the user, and include a privacy policy in the app.

“Additionally, if an app collects and transmits personal data unrelated to the functionality of the app then, prior to collection and transmission, the app must prominently highlight how the user data will be used and have the user provide affirmative consent for such use,” the announcement said.

Google also warned developers against underhanded behaviour in crash reports: “the list of installed packages unrelated to the app may not be transmitted from the device without prominent disclosure and affirmative consent.” ®