An Android in Every Home - Beginning Android Games - page 5

Google Play allows third-party developers to publish their programs either for free or as paid
applications. Paid applications are available for purchase in many countries, and the integrated
purchasing system handles exchange rates using Google Checkout. Google Play also gives the
option to price an app manually on a per-country basis.

A user gets access to the store after setting up a Google account. Applications can be purchased
via credit card through Google Checkout or by using carrier billing. Buyers can decide to return
an application within 15 minutes of the time of purchase for a full refund. Previously, the refund
window was 24 hours, but it was shortened to curtail exploitation of the system.

Developers need to register an Android developer account with Google, for a one-time fee of
$25, in order to be able to publish applications on the store. After successful registration, a
developer can start publishing new applications in a matter of minutes.

Google Play has no approval process, instead relying on a permission system. Before installing
an application, the user is presented with a set of required permissions, which handle access to
phone services, networking, Secure Digital (SD) cards, and so on. A user may opt not to install
an application because of permissions, but a user doesn't currently have the ability to simply
not allow an application to have a particular permission. It is “take it or leave it� as a whole. This
approach aims to keep apps honest about what they will do with the device, while giving users
the information they need to decide which apps to trust.

In order to sell applications, a developer additionally has to register a Google Checkout
merchant account, which is free of charge. All financial transactions are handled through this
account. Google also has an in-app purchase system, which is integrated with the Android
Market and Google Checkout. A separate API is available for developers to process in-app
purchase transactions.

Google I/O
The annual Google I/O conference is an event that every Android developer looks forward to
each year. At Google I/O, the latest and greatest Google technologies and projects are revealed,
among which Android has gained a special place in recent years. Google I/O usually features
multiple sessions on Android-related topics, which are also available as videos on YouTube's
Google Developers channel. At Google I/O 2011, Samsung and Google handed out
Galaxy Tab 10.1 devices to all regular attendees. This really marked the start of the big push by
Google to gain market share on the tablet side.

Android's Features and Architecture
Android is not just another Linux distribution for mobile devices. While developing for Android,
you're not all that likely to meet the Linux kernel itself. The developer-facing side of Android is a
platform that abstracts away the underlying Linux kernel and is programmed via Java.
From a high-level view, Android possesses several nice features:

ï?® application framework that provides a rich set of APIs for creating
various types of applications. It also allows the reuse and replacement of
components provided by the platform and third-party applications.

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