I have a Galaxy Note 3 with a Zero Lemon battery, and the sweet spot is absolutely tiny. Tiny enough that it makes it a pain to use. When I finally figured out where the sweet spot was (which was like I said, tiny), I threw my Facebook URL on one side to play around with. I walked around my workplace trying it on different phones, and finding the sweet spot on each phone made it a little ridiculous honestly. I love this ring, the looks and quality of it is superb, but it just isn't performing like I expected it would. I read a few places where the alpha ring performed better since most of the phones nowadays have such large NFC antennas. Has anyone found that to be the case?