You can't customize the Quick Settings in stock Android (although I can't speak specifically about the One). You might like Power Toggles, which allows you to place a customizable toggle bar on the homescreen or in the notification shade.
Interesting that htc chose to leave this out. My note 3 id bone stock and can customize the quick toggles
dpham00, Android Central Moderator
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You can. There are 20 options of which up to 12 can be used at a time
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Yea unfortunately we're subject to the whim of our makers lol
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Crazy isn't it. First we have Google with base android. Then you have the phone companies that want there own version of a UI. Then we have the cell providers that have to tweak the the phone companies version of Google's operating system.
Well that's a lot of fingers in a little ol' phone
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The reason (I'm guessing here) that NFC isn't one of the selectable quick toggles in Sense is that android doesn't allow quick toggling of NFC. I've read it's a security issue. You can put the NFC toggle in power toggles (as shown above), but without rooting it won't actually turn NFC on and off, it just takes you to the settings menu so you can to it yourself.
The reason (I'm guessing here) that NFC isn't one of the selectable quick toggles in Sense is that android doesn't allow quick toggling of NFC. I've read it's a security issue. You can put the NFC toggle in power toggles (as shown above), but without rooting it won't actually turn NFC on and off, it just takes you to the settings menu so you can to it yourself.