Detect if app was downloaded from Android Market

Question

I have an Android library that uploads data to a test server and production server. I'd like developers using this library to use the test server when developing, and production server when the app is downloaded from Android Market.

Is this possible for an app to tell where it came from (Market or non-Market?) I would imagine one could detect the presence of the signed JAR file.

Answer 1

Yes, you could use the signature for that. If you use a debug key to sign your app during development and a release key when uploading your app to the market you can check for the signature that the app was signed with and based on that use test or production server. Here is a small code piece to read the signature of your app:

    try {
        PackageManager manager = context.getPackageManager(); 
        PackageInfo appInfo = manager.getPackageInfo(
            YOUR_PACKAGE_NAME, PackageManager.GET_SIGNATURES);

        // Now test if the first signature equals your debug key.
        boolean shouldUseTestServer = 
            appInfo.signatures[0].toCharsString().equals(YOUR_DEBUG_KEY);

    } catch (NameNotFoundException e) {
        // Expected exception that occurs if the package is not present.
    }

YOUR_PACKAGE_NAME must be something like 'com.wsl.CardioTrainer'. It must be the package name you used in your AndroidManifest.xml. Good Luck

mark

Answer 2

Starting with API 5, you can use PackageManager.getInstallerPackageName(String). From the documentation:

Retrieve the package name of the application that installed a package. This identifies which market the package came from.

To get the package of the Android Market, this post may help.

Answer 3

From what I can tell there is nothing that the Market Application does to "flag" an application to say that it was downloaded from the market.

I have seen this issue approached in a different manner by another Android library. The AdMob Android SDK is free to download and use as described on their wiki. This library serves ads, so they have the same desire to be able to determine if the application that is currently running is being tested by the developer or if it is being used "in the wild". Their approach was to require that the developer set a "testing" attribute in the XML or to call their libraries "setTesting(boolean)" function to let the library know which ads to serve. This is obviously more of a manual approach that relies on the developer to change one line of code or XML before publishing.