SpeaktoIt seems to have more personality based off responses it gives. It is not as serious as Siri. Though Siri does have its Easter eggs too though less so

SpeaktoIt seems to have more personality based off responses it gives. It is not as serious as Siri. Though Siri does have its Easter eggs too though less so then speak to it. Both are equally useful and enjoyable and have their strengths and weaknesses. Siri is built into iPhone and it's speech is superior to speak to it.