About Google Play App Signing

Question

When I login to my Google Play developer Console, I see this:

I understand how Google Play App Signing works, in general it keeps the app signing key on behalf of you, and I need to use another so called "upload" key to sign my app and submit to Google Play Console for app signing.

But, my question is:

I already published my app without using Google Play App Signing half year ago, now, if I opt-in to Google Play App Signing, would it affect my already released app? Or Does it go smoothly with my published app if I switch to Google Play App Signing?

Answer 1

Would it affect my already released app? Or Does it go smoothly with my published app if I switch to Google Play App Signing?

No, it will not affect your already released app. It will go smoothly with your already published app if you switch to Google Play App Signing.

But once you opt in Important: App Signing opt-in is permanent.

I did the same for few of my apps in the past and all are working fine.

Once you opt-in your original app signing key is uploaded to Google Play and you will be signing your new build with the newly generated upload key.

Further updated build will be signed locally or on dev machine via upload key. After uploading signed locally build the to Google Play, the Google play will remove your key and will sign the apk once again with your original app signing key.

Existing apps

Answer 2

Google app signing works perfectly with the existing apps and your app doesn't get affected if you enroll now. I am listing the steps that may help you to enroll without any difficulties.

1) Sign in to your Play Console and select your app.
2) On the left menu, click Release Management > App Signing.
3) Upload your existing key and follow the rest of instructions.

P.S. Once you opt in for Google app signing, you can't opt out.