Google Play has issued a letter to developers to offer advice on building better and more secure apps.
The letter said that Google had made changes to its policies in regard to ‘dangerous products' that disclose personal information without authorisation and the behaviour of adverts in applications.
Google said that it is providing more detail on the kinds of dangerous products that are not allowed on Google Play, and has added a new section that addresses advert behaviour in apps.
It said: “First, we make it clear that adverts in your app must follow the same rules as the app itself. Also, it is important to us that adverts don't negatively affect the experience by deceiving consumers or using disruptive behaviour such as obstructing access to apps and interfering with other adverts.â€
This policy states that adverts are considered part of the app for the purposes of content review and compliance with the developer terms, so all policies, including those concerning illegal activities, violence, sexually explicit content and privacy violations, apply.
In terms of the context of adverts, Google said: “It must be clear to the user which app each ad is associated with or implemented in. Adverts must not make changes to the functioning of the user's device outside the ad by doing things such as installing shortcuts, bookmarks or icons or changing default settings without the user's knowledge and consent.
“If an ad makes such changes it must be clear to the user which app has made the change and the user must be able to reverse the change easily, by either adjusting the settings on the device, advertising preferences in the app, or uninstalling the app altogether.â€
Also, adverts must not simulate or impersonate system notifications or warnings and adverts associated with an app must not interfere with any adverts on a third-party application, it said.
Research by MWR Infosecurity and Channel 4 News found that some leading applications were sending personal data back from devices to advertising companies without user knowledge and that permissions were granted to the apps when they were downloaded.
Updating its Google Play developer program policy, Google said that it is required to update its policies when it launches new features and when it sees unhealthy behaviour such as deceptive app names and spam notifications.
It has also restricted the use of names or icons that are "confusingly similar to existing system apps in order to reduce user confusion". It said that any existing apps will be given 30 days to fix and republish the application and after this period, existing applications discovered to be in violation may be subject to warning or removal from Google Play.