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Sidebar: Piracy Protection
The existence of the Windows Store and the fact that users cannot install an app except in the
context of the Store provides a certain inherent level of piracy protection. Users are blocked from
accessing the folders that contain installed appx packages, and even if they managed to extract
and install one elsewhere, the Store would report that the app is unlicensed for that user and
would thus refuse to run it.
Beyond that, any additional levels of protection are up to the app. It’s perfectly allowable for
an app to ask the user to register with the publisher (because customer information isn’t shared
from the Store) and to obtain a secondary license key. Windows does not block such procedures
but doesn’t provide any such services itself. Do consider, however, that customers might be
annoyed by such additional requirements. It’s best to exercise caution in such a decision.
In-App Purchases
In-app purchases are a primary means to monetize an application over time by selling incremental
add-ons, options, periodicals, time-limited subscriptions/rentals, and so forth. By definition, the lack of
any such options cannot interfere with the core operation of the app. In-app purchases cannot also be
interdependent—that is, users cannot be required to purchase other options to use one they’re already
bought. Know too that an app is limited to 100 such in-app purchases when they are managed through
the Windows Store; if you use your own commerce engine, as described in the next section, there is no
such limit.
Whether in-app purchases are the right choice for your app involves a number of considerations:
• Implementing them well can be difficult because they introduce complexities into an app’s
architecture. (Note that Windows does maintain information for in-app purchases that can
expire.)
• The app has full responsibility for correct delivery of the purchased item or feature, as opposed
to the Store handling all the details.
• In-app purchases effectively create multiple variations of an app, which can increase user
support and interaction.
• Overuse or inappropriate use of in-app purchases can generate the perception that you’re trying
to get money from users at every possible opportunity. Users who don’t or won’t pay for in-app
purchases can still leave bad reviews about their experience.
• At present, the Windows Store supports only “durable” products (that can be purchased only
once until they expire); there is no support for “consumable” products that can be repeatedly
purchased. Consumables are under consideration for future versions; at present they can be
implemented by using a custom commerce engine.
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