iOS 11 comes with a very interesting accessibility setting for the Siri personal assistant, Apple allowing voice commands to be typed in its interface. In the image below you can see how everything looks, iOS 11 showing the menu for entering texts, plus an extremely interesting dark interface, which should be available everywhere.
Returning to the topic, This new function of Siri in iOS 11 is implemented especially for those who have speech impairments, but it can be useful in other situations as well. More precisely, if you are in a crowded area where Siri will not understand, or where you do not want to speak the commands, you can quickly write them using this new function available in iOS 11.
The new function of writing commands for Siri in iOS 11 can be activated from Settings > General > Accessibility > Siri, Configurations > General > Accessibility > Siri, only if you have Siri activated beforehand.
