Allow automatic updating android market
To prevent apps from automatically updating, touch the “Do not auto-update apps” option.
NOTE: If you want apps to update automatically, but you want to avoid going over your data limit, touch the “Auto-update apps over Wi-Fi only” option.
If you would rather review the updates and any new or changed permissions associated with the updates, you can choose to disable automatic updates.
Nevertheless, a common option is to host on web server the last version number, check it at app startup and offer an update if one is available (via a market link intent).
You can also use some of the update strategies like status bar, popups or silent updates for rooted devices.
By default, Android apps downloaded from the Google Play Store are automatically updated.
Is there an example of something like this out there?
at the start of your app check the available version, the you can use an Alert Dialog to ask for the upgrade.