We have several developers working on Android, so it is just behind.
Is the change in voice memo only affecting users on iOS with the new app, not Android?
Correct, there will be no change in how voice memos are processed for Android users until the new Android app comes out.
What should I do with the Capture app?
The Capture app will continue to function for now and we will update on that once we have the new app approved in App Store. If you are happy with the new app after testing it, you can just delete it.