What was once deemed the "Wild West" of apps stores, Google's Google Play appears to be refining its policies some in an effort to give the store a bit more civility. 

In a letter, Google alerted developers to changes made to its Developer Distribution Agreement (DDA) posted on its website. The changes appear to reinforce the store's content rating guidelines, while more clearly explaining terms such as “hate speech,” “gambling” and “dangerous products,” as well as providing further guidance around areas such as payments, malware and spam.   

The posting also makes explicit that any application must play nice with the network, stating that "applications must not create unpredictable network usage that has an adverse impact on a user's service charges or an authorized carrier's network." Applications also may not knowingly violate an authorized carrier's terms of service for allowed usage or any Google terms of service.

Google also solidified its policies around ads that are implemented in and bundled with apps. The company said in the post that the rules are important in maintaining a positive experience for users and advises developers to check back for changes in these policies. 

Specifically, developers are advised to ensure that that ads associated with their apps are consistent with their content rating and 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. 

Google has also clarified its stance on payment issues. Developers charging for applications and downloads from Google Play must do so by using Google Play's payment system.  

Meanwhile, those developers offering additional content, services or functionality within an application downloaded from Google Play must use Google Play's payment system as the method of payment, except where payment is for physical goods or services or where payment is for digital content or goods that may be consumed outside of the application itself. 

And these aren't just empty promises by Google. The company states that serious or repeated violations of the DDA will result in account termination.