Siri just gets better and better. Now, with iOS 9 You can say “Hey Siri” even if your phone is not plugged in. It will only respond to your voice and you need to put the option in place. Before you can use the “Hey Seri” option you have to set it up so it recognizes your voice. Go to Settings> General > Siri. If it is not active change the button to green and select Activate. (If it is already green, just turn it off and back on. The setup option will appear.) You will be asked to speak several specific phrases into your phone and when it is set up properly it will tell you it is done. Then you can do things like ask Siri “Hey Siri, Where is my Phone”, or What is the “weather forecast”. If you have a web page open on your phone you can tell Siri “Remind me of this when I get home. You can also open many accessibility features just by asking Siri to (Turn on (feature).
Siri can do basic sums and a few other math options. She can convert measurements (miles to kilometers) or monetary values (American dollars to English pounds.) You must preface your request with “Convert….)