Yes different version code but the APK must work in a different device. Like i said android 4.4 is not the same like android 5 or newer models. Phones with android 7 or better have more stuff than android 5 or less. So in a easy to understand way:
android phones 4.4 are different than newer models which require more understanding on them. This could be version code 11111
android phones 5 or newer are common and very targeted because it has greater specs than 4.4 or lower. This could be version code 22222
android 7 and newer have finger print secrtity, better spec than android 5 and is offen used by richer people. This could be version 33333
Then you have android watch, if you program it right that could be version 44444
Android car version could be 55555
The list goes on, When they ask for different version code it is only used to help google fit in the right code. A article explaining it in more detail: https://medium.com/@maxirosson/versioning-android-apps-d6ec171cfd82