<manifest>

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
          package="string"
          android:sharedUserId="string"
          android:sharedUserLabel="string resource" 
          android:versionCode="integer"
          android:versionName="string" >
    . . .
</manifest>

xmlns:android

Defines the Android namespace. This attribute should always be set to "http://schemas.android.com/apk/res/android".

package

A full Java package name for the application. The name should be unique. The name may contain uppercase or lowercase letters ('A' through 'Z'), numbers, and underscores ('_'). However, individual package name parts may only start with letters. For example, applications published by Google could have names in the form com.google.app.application_name.

The package name serves as a unique identifier for the application. It's also the default name for the application process (see the <application> element's process process attribute) and the default task affinity of an activity (see the <activity> element's taskAffinity attribute).

android:sharedUserId

The name of a Linux user ID that will be shared with other applications. By default, Android assigns each application its own unique user ID. However, if this attribute is set to the same value for two or more applications, they will all share the same ID — provided that they are also signed by the same certificate. Application with the same user ID can access each other's data and, if desired, run in the same process.

android:sharedUserLabel

A user-readable label for the shared user ID. The label must be set as a reference to a string resource; it cannot be a raw string.

This attribute was introduced in API Level 3. It is meaningful only if the sharedUserId attribute is also set.

android:versionCode

An internal version number. This number is used only to determine whether one version is more recent than another, with higher numbers indicating more recent versions. This is not the version number shown to users; that number is set by the versionName attribute.

The value must be set as an integer, such as "100". You can define it however you want, as long as each successive version has a higher number. For example, it could be a build number. Or you could translate a version number in "x.y" format to an integer by encoding the "x" and "y" separately in the lower and upper 16 bits. Or you could simply increase the number by one each time a new version is released.

android:versionName

The version number shown to users. This attribute can be set as a raw string or as a reference to a string resource. The string has no other purpose than to be displayed to users. The versionCode attribute holds the significant version number used internally.