Turns out I don’t have Proguard activated on a live app that I have published to the Google Play store. It’s not the end of the world since I don’t have anything sensitive in the app (and I’ve found that I can decompile apps pretty well even when Proguard is applied).
My question is: If I apply Proguard and then upload a new .apk to Google Play, when my users update are they going to run into a problem?
One reason I ask is because I learned the hard way that changing the LAUNCHER activity in an app can make user-created shortcuts void in an updated version, so I’m trying to prevent causing any more inconvenience to my users.
No. You users are getting a compiled version of your application, not the raw sources.
As long as the package name remains the same and you sign the package using the same keystore you won’t have any problems.