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It looks like a good idea, but it isn't always accurate. I've had it on my phone for a couple of weeks and check it at different places to see if I get the same 3 words and often I don't.
Phone GPS can be inaccurate so can move across a number of squares. If you try zooming in until you see the grid and then selecting the square you want to reference. That square will always have the same 3 word address. Great for remembering that perfect fishing spot! 
Thanks, I'll try that next time I'm out.
I've been trying it in various locations and found the trick is to tap the reset icon several times until it it sticks with the same 3 words. |This can take a couple of taps or half a dozen, but does appear to give very good consistency.
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