If you still wish to experiment with the legacy NullDC APK for historical interest, follow these general steps. Note that compatibility with modern versions of Android (Android 12 and above) may be extremely limited.

The original Android port was in alpha stages around 2010 and was quickly superseded by Reicast.

: Go to Settings > Security on your device to allow APK installations from your browser or file manager.

NullDC was originally a highly regarded, open-source Dreamcast and NAOMI emulator developed for Windows. In late 2010, an alpha version was ported to Android, showing early promise for mobile Dreamcast emulation.