Auto-Update for (private) Android apps

Question

I'm developing a non-public Android app, i.e. the app won't be available in the global Android Market. The app will be installed on a limited number of clients, e.g. by using an apk file. How can I enable an auto-update functionality in this app?

I see different potential options (I do not know if those are technically hard or even impossible to implement or if there are any existing functionalities that can be reused):

• On each launch the app tests if a new version exists (by requesting a server), if so downloads the new apk and replaces itself with the new version.
• Use (or develop?) a separated app or service that undertakes the update-check and replacement-process.
• Use (or develop?) a private market app which has an auto-update option. This option is similar to the second one, but more generic: The market app would be connected to a repository, i.e. it would handle an arbitrary number of (private) apps.

I would prefer option one since the auto-update functionality is included in the app which needs less development efforts.

Answer 1

janjonas, in the company I work we had a similar problem with Windows Mobile 6.x, and we use pretty much the same solution pointed by EboMike:

The main app check if it's updated, against a WebService. It receives the current version & the URL from where download the new version, if necessary. The main app then start the Updater app, passing the URL, and quit.

The Updater do the download of the new program, via HTTP, showing to the user the % downloaded. The user can cancel the download anytime, in a controlled way, and the Updater can registry this cancellation.

Since the new app is downloaded, the Updater run the new app, and quit.