What I believe you are trying to ask is how to subscribe your application to intents for launching web URIs. In order to do so, you can add an intent filter to your application's manifest.
There's an example of this on Lars Vogel's blog. It boils down to this:
<application android:icon="@drawable/icon" android:label="@string/app_name">
<activity android:name=".BrowserActivitiy"
android:label="@string/app_name">
<intent-filter>
<action android:name="android.intent.action.VIEW" />
<category android:name="android.intent.category.DEFAULT" />
<data android:scheme="http"/>
</intent-filter>
</activity>
</application>