Republishing/distributing an Android app after losing keystore

Question

I am about to republish my Android app with a new package name, since I lost my previous keystore. I would like to distribute the new .apk to all buyers of the "old" app. But how can I do this? Can I find their email addresses somewhere? I've searched everywhere at the Google Wallet Merchant Center for email addresses... but no luck.

Also, will these users be able to receive future updates, if they installed my "new" app with the .apk?

Answer 1

How can I find buyers of old app ?

• Go and check with google wallet the email addresses who have paid
• If you were maintaining some login then some details must be on your server itself

Will these users be able to receive future updates, if they installed my "new" app with the .apk?

• You must publish your app i.e. signed with the actual certificate that you will use on google play and then email the same to every user , then only the users will be able to receive updates from google play