Why did user data becomes large after moving to android bundle?

Question

due to the 64-bit support; I've switched from uploading APK to uploading bundle to Play Store. However I noticed that although the APK have been getting smaller, the "User data" size (view from phone's settings) have now becomes much larger. Below are an example for my app:

Using APK:

• Total: 105MB
• App size: 102MB
• User data: 504KB
• Cache: 3.21MB

Using Bundle:

• Total: 45.34MB
• App size: 5.02MB
• User data: 39.14MB
• Cache: 1.18MB

Although I can understand why the App size is much smaller (Play Store only downloads what is needed by the device), I'm curious what exactly causes the User data to becomes this large? Did Play Store treats the components needed to be downloaded as User data?

*Not sure if it's related, but the app was built by using React Native.

Answer 1

I had a little reading about APK. vs. Bundles and based on what I understood, APKs have all of the app's files and code inside while Bundles have all the DATA and basic settings needed to run your app...

this shall answer your question :)