APKs are for Android TV OS based TVs. The last APK available can be found here but I don’t know if they would work on your specific TV Plex for Android - #525 by PlexAndroidReleaser
We don’t make an app specific to JVC. If not Android based they may have had our generic Smart TV app though Smart TV Alliance. Though they may not use that anymore so it may not be in their store/market any longer even if you had it previously installed.
