Google has been adding new monetization features to the Play Store over time, and one of the more contentious is, of course, the in-app purchase. You know how it goes; an app is free and things are good until the upsell comes. What you may not know is that there are several different kinds of in-app billing on Android, and some of the strange wrinkles in Google’s app ecosystem make it hard to know what you’re really getting. If you know the basics, you can save yourself headaches, as well as money.

Managed purchases

It is not always clear what kind of content you’re buying when an app offers an in-app purchase. As a rule of thumb, if you are buying game levels, the full version of an app, or expansion packs, you are making a managed purchase. These transactions are the safest and lowest hassle of any Android in-app purchase.

A managed purchase is called that because it is managed by Google on a per-account basis. Whichever account you are logged into under in the Play Store, that is the account that you will attach the content to. Assuming that the developer does not unpublish the files, you will be able to transfer that purchase to other devices by simply logging in.

Unfortunately, some apps will take time to retrieve any managed content you have purchased. You might open an app and find that it still has ads or your expansion levels are missing. After a few minutes, the Play Store should have everything worked out, but a device restart might be needed. Some developers kindly include a menu option to trigger the “restore_transactions” request manually.

The bottom line is that managed purchases are yours forever, but that’s not always the case with in-app billing.

Unmanaged purchases

If one of your games or apps presents you with a buffet of consumable point packages, odds are you’re looking at an unmanaged purchase. Games from developers like Glu Mobile and Zynga encourage users to buy in-game currency to pay for upgrades and items. By going this route, the developer effectively locks users into a little pseudo-economy.

These transactions are called “unmanaged” because Google does not manage your access to the content on its servers. Once you buy a bucket of in-game credits, upgrade points, or whatever else, they live only on your current device. That means you’ve spent money on something transient and easy to lose. A good way to tell when an app is selling you unmanaged content is that you are able to buy the same item multiple times, as you would with buckets of in-game currency.

The content bought in this way is saved in your app data; clear that, and you’ve lost everything you bought. If you install the app on a second device, you won’t get anything bought with in-game points restored, nor will unused points return. In fact, even uninstalling the app will clear all your unmanaged purchases forever as well. There is no restoring of consumable items.

You may be wondering about backing up your app data, and it is possible, but not convenient. On Android 4.0 and higher, there is a manual application backup module that can be used to save the app itself as well as the data. You need to be familiar with the command line, and I’ve found the restore process to be imperfect, but it can save your paid-for items. Rooted users can use tools like Titanium Backup to do the same thing with more ease.

Google doesn’t have any kind of full device backup like Apple does, but it has offered developers the ability to sync app data to the cloud since Android 2.2 Froyo. Unfortunately, very few developers take advantage of it. Out of roughly 200 apps on my phone, only three third-party apps take advantage of this feature.

So in the case of unmanaged purchases, don’t uninstall the app, don’t clear the data, and don’t expect to get your bought items on more than one device. Many developers will happily sell you $50 worth of in-app points knowing full well you can only enjoy them until you get a replacement phone, or uninstall the app.

Next page: In-app subscriptions