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Both thumbs and both index fingers. The thumbs each registered as their own finger, while both index fingers only took a single slot, because I'm a hoarder :D In case you're wondering how that's done, when you scan your finger just alternate your left and right hand. It's easier to unlock using the index finger when the phone is laying on the table.

I did this using 1 space. I rotated between right thumb, right index, left thumb, left index, back to right thumb again... I have 1 slot and can use 4 fingers, works just as fast with any of them.

5s (waiting on my 6+)
 
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