Developer Steven Troughton-Smith (@stroughtonsmith) managed to port Siri to the iPhone 4! But as you can see in the video below, its really laggy. The reason being is that the hack is currently missing an iPhone 4 GPU driver. Also, while Siri currently can recognize spoken commands, Apple wonâ€™t authenticate Siriâ€™s commands coming from an iPhone 4. Obviously, this hack isnâ€™t ready to be released, but chances are we will be able to install Siri on our iPhone 4 very soon.