Google has quietly added a new feature to the Play Store that allows you to set and manage your budget for premium apps, books, movies, games, and in-app purchases. The new budgeting feature by no means imposes an absolute limit on your spending, though, as it's only meant to help you monitor how much you have spent on items within the app store.
To set a budget, simply open the Play Store app on any Android device and tap the hamburger menu. Go to "Account" and then to "Purchase History". From there, you can assign an upper limit to your budget.
The new capability lets you receive a notification informing you if your spending is close to or beyond your set budget. Google says you can only set a budget in the currency of your current Google Play country profile. For now, the feature only works on the Play Store app on mobile devices.
In addition, there's an option to change or remove your set budget by heading over to your order history and then tapping the appropriate button. Also, you can review your spending in the same section. The feature appears to be rolling out in stages as it doesn't seem to be live for everyone just yet.