One very attractive feature of the Android platform is that it lets developers skip the Android Market completely and distribute apps directly to users. This is a great option in many situations. For example, a corporate IT department might want to distribute a private app to employees. Or maybe you want to run a private beta of your app before uploading it to the Android Market.
Whatever the case, direct distribution couldn’t be easier: upload your signed .apk binary to your web server and provide your users with a link to it. Users click the link—say, from an email message or a web page—and the app is downloaded and installed. Simple.
Note: You can also use QR codes to distribute links to your app. A QR code is a two-dimensional barcode that can store up to 4,296 alphanumeric characters of arbitrary text and be read by the camera on an Android phone. When a user encounters your QR code, she can take a picture of it with Google Goggles (or another QR code reader app), and she’ll be provided with a link to your app. You can learn more by visiting the Google Chart Tools page devoted to QR codes. You can create your own for free using Google’s Live Chart Playground.
The only caveat is that users have to first allow installation of non-Market applications by navigating to Settings→Applications and enabling the Unknown Sources option (
Figure 8-5). If the user has not first enabled downloads from unknown sources, he will still be allowed to download the app, but will be alerted that the install is blocked (
Figure 8-6). The alert dialog will allow him to navigate directly to the relevant setting or cancel the installation. When the user first activates the checkbox, he’ll see a confirmation dialog that warns him about the implications of his choice (