Google sent out a mail earlier today to developers informing them of new Google Play Developer Program Policy Updates. The mail, which was also sent to Neowin, included updated guidance for apps that seek to monetize the lockscreen, updated content rating guidelines for unrated apps, and clarification for program requirements for Designed for Families. Of the three, the first is quite interesting. The new guidance reads:
Unless the exclusive purpose of the app is that of a lockscreen, apps may not introduce ads or features that monetize the locked display of a device.
Which basically means that any app that isn't specifically a lockscreen app can no longer place ads on the lockscreen of your Android smartphone. Android Police, which has been trying to, er .. "police" the issue for quite some time, gave some examples in their post earlier today.
According to Android Police, ads started showing up on the lockscreen feature of previously safe apps like ES File Explorer, Peel, and Hotspot Shield VPN, and once that started happening it opened a can of worms for other apps that rely on "in-app purchase" or are just plain naughty.
So to clarify from the above examples, an app that bills itself as a file explorer, photo editor or VPN cannot also place a new lockscreen on your device that includes ads. The policy change is already live, so if there are apps out there still doing it, and are not listed in the Play Store specifically as a lockscreen app, they can be reported and Google will have no option but to remove the listing.
Source: Email, Android Police