Running a PS4 emulator on an Android device with 1GB RAM is highly challenging, if not improbable. The emulator would require a substantial amount of RAM to mimic the PS4's 8GB of RAM, not to mention the processing power needed to handle the complex graphics and gameplay.
Many developers create mobile versions of PS4 games. These aren't emulators, but rather separate apps built specifically for Android. Ps4 Emulator For Android 1gb Ram