As a workaround we added the following to our own manifest:
<provider
            tools:replace="android:authorities"
            android:name="com.google.android.gms.measurement.AppMeasurementContentProvider"
            android:authorities="${applicationId}.google_measurement_service"
            android:exported="false" />

You must have tools namespace defined in the xml.

I've also been affected by this!

@2 I also opened an issue with tools guys https://code.google.com/p/android/issues/detail?id=193567 . I'm not really sure which team should fix it. There's another workaround there that in my opinion is cleaner.

I've added 
android {
    defaultConfig.applicationId = "my.package.id"
}

to my gradle file and it fixed that issue for me

Setting android.defaultConfig.applicationId in your gradle file is something that is expected to be set in Android projects. This is automatically added when you create a new Android project in Android Studio.

However when applicationId isn't present in the project gradle the play-services-measurement AAR package in its AndroidManifest.xml gets defaulted in. This creates a silent issue for the app developer as their is no warnings or errors when the app builds. Only after another app that was build the same way is also installed on the device is the issue known as the OP noted with the INSTALL_FAILED_CONFLICTING_PROVIDER error.

The fix is adding android.defaultConfig.applicationId to your app's gradle file as others have noted however, the play-services-measurement AAR or the build tools should be changed to throw an error if this is missing.

In cordova generated projects android.defaultConfig.applicationId is missing

I have already opened an issue with Cordova on this not being adding by default and have provided a work around to set android.defaultConfig.applicationId in the comments until Cordova fixes this.
https://issues.apache.org/jira/browse/CB-10014

Thanks for the solution in #4 - that worked for me!

Are these apps successfully uploading to the play store? And users of the apps are seeing this error?

I'm wondering if the play store checks for authorities uniqueness to ensure this doesn't happen on a wide scale.

#4 did the trick.

The users only see an errormessage with code 505, an errormessage that is given for other installation-failures as well. 

Error persists in Google Play Services version 8.4.89 (2428711-230).

Two apps I use are in conflict as described above in original post.

RadPad and Glassdoor.

Uninstall one, the other will install.

Any workaround for us users?

#12, You can try using older version and send feedback to the developers and hope they will fix it fast

#4 is the perfect solution, you saved my day!

I'm desperately requesting your help.

I'm having some users complaining about Play Store Error 505.
I cannot apply solution #4 because my project is a library project, so I'm getting: "Error: Library projects cannot set applicationId."
My app is currently using Play Services 8.3.0. Does anyone know what else I can try? Thanks in advance!

#15, who is using your library? he should set the app id.
Do you declare authority provider in your lib?

I could reproduce and fix this issue. This is referred in the following thread: 
https://goo.gl/UvjIVk

Good luck & thank you.

There's no gradle support in Intel-XDK yet, due to security issues. Is there another way around to solve this problem without gradle? 
Many thanks, 

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