Google updates Play Store policy says that apps can only update via the Play Store

Google has added a new policy to app submissions in the Play Store guidelines that any app uploaded to the Play Store can only be updated through it and not through any other source. 

The change is a part of the "Dangerous Products" section of the Google Play Developer Content Policy, and says:

An app downloaded from Google Play may not modify, replace or update its own APK binary code using any method other than Google Play's update mechanism.

The reason for the new policy can be Facebook's way of bypassing the Play Store when it said that Facebook Home updates will be pushed directly to users instead of through the Play Store. So its unclear what Facebook will do at this time, but at present it does not have a choice but comply with the new guidelines. 

But it should be noted that no apps were previously allowed to push updates without going through the Play Store and without notifying to the user about new permissions that the update may require. Therefore, its just something that has been put into writing now, but has been in existence wince the Play Store was launched.

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