They a very similar Harry. Of course you can do things with Siri like dictate text messages and emails that Alexa cannot do. However you can ask Alexa to play music, look up answers to questions, and control home items like lights, switches, thermostats, etc. Siri can also do that. I too use Siri on occasion, and I think it can probably do more, but Siri has been around a long time compared to Alexa so it should be way more advanced and polished. The one main difference in Alexa is that if you use an Echo or Dot then you can just say "Alexa, do ..." rather than having to pull out your phone or tablet and physically activate Siri (or Alexa on Tap/phones/tablets/Fire TVs).