Google updated the developer policies for apps distributed via its Play store, including significant changes to its position with regard to billing and advertising.

According to the company, its intention is to “foster a high standard of app behaviour, so you will be able to take advantage of Google Play as a successful platform to distribute your apps and continue to grow your business”.

In a post, Google said that developers charging either for app downloads or via in-app purchases “must use Google Play’s payment services”, although there is an exception for apps where payment is primarily for physical goods or services, or for “digital content or goods that may be consumed outside of the application itself”.

While the search giant has been offering its own payment mechanisms for some time, it has not previously mandated its use. It is not clear if it has now completely closed the door on third-party payment enablers, although the terms certainly seem to imply this.

It has also updated its advertising policy, including a “system interference” section which limits the use of advertising beyond the app itself.

It said that developers “must not make changes to the user’s device outside of the app without the user’s knowledge and consent”, including replacing or re-ordering the default presentation of apps, widgets and settings, and that if it does so with consent, the user must be able to reverse this “easily”, or by uninstalling altogether.

Apps must also not add homescreen shortcuts, browser bookmarks, or icons to a device “as a service to third parties or for advertising purposes”, and must not use system-level notifications to serve adds “unless the notifications derive from an integral feature provided by the installed app”.

Requiring users to click on ads or submit personal information for advertising purposes in order to fully use an app is now prohibited, and a “prominent and accessible” target must be provided in interstitial ads, so users can dismiss them “without penalty or inadvertent click-through”.

The Next Web also said that Google has introduced a “revised hate speech policy that provides more comprehensive coverage, while recognising Google Play’s role as a platform for free expression”.

The changes are likely to create a significant amount of work for developers with apps already available, to comply with the new terms.

TechCrunch also said that Android developers can now make free apps available in Iran, although paid for titles and those which use in-app purchases remain verboten.

The report noted that Google and the Iranian authorities have a somewhat troubled relationship. The internet company’s services, including Search and Gmail, have been closed down previously (with YouTube still unavailable), and it has previously said that it uncovered an Iranian spy campaign which targeted voters through phishing emails.