Both can technically contain Java MIDlet (Mobile Information Device Profile) code. The .vxp is often just a .jar file with a different header, encryption, or a manifest signature.
If these are missing, your .jar is not a mobile app and become a .vxp . Convert .jar To .vxp UPD
| Problem | Likelihood | Solution | | :--- | :--- | :--- | | Device says "Invalid VXP" | Very High | Your file lacks Vodafone encryption. Use a VXP packer tool. | | App starts but screen is glitched | Medium | Adjust LCD size settings in the VXP manifest. | | No sound | Medium | Convert audio to Vodafone-supported format (e.g., 8-bit PCM). | | App crashes on load | High | The .jar uses APIs not present in Vodafone's limited runtime. | Both can technically contain Java MIDlet (Mobile Information
def convert_thread(): self.progress.start() try: output_path = Path(self.jar_path.get()).with_suffix('.vxp') package_id = self.converter.create_vxp_package( self.jar_path.get(), str(output_path), self.create_upd.get() ) | Problem | Likelihood | Solution | |