In iOS 7, Siri can toggle a lot of settings: Bluetooth, Airplane Mode, Wi-Fi, and more. And the virtual assistant also gives quick access to more granular settings.
Tell Siri something like, "Change the brightness," and the brightness slider will appear onscreen, ready for you to adjust. Of course, you could always simply drag up Control Center instead, but who doesn't like a virtual minion to do their brightness-adjusting bidding?
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