Sure, iOS will give you a quick hint as to what you can ask Siri , but there’s a lot more the voice control system will recognize. How do you know whether or not your command will work? You don’t have to guess. Sandro Roth’s recently launched Hey-Siri.io outlines a whopping 489 Siri actions for both iOS and the Mac , all of it neatly divided into categories with practical examples. If you want to know how to talk to your smart home devices or create a grocery list, the answer is likely just a few taps away. This probably won’t cover absolutely every command (certainly not those for third-party apps ), but it could save you a lot of guesswork… not to mention embarrassment. Source: Hey Siri
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Siri cheat sheet shows how you can talk to your iPhone