Get it from ebay, b a n g g o o d or aliexpress.com. I got mine from aliexpress for 2.70 USD. You can choose different colors. My clip is gold plastic an the lenses are gold aluminium
It works with the iphone 6 and other mobile phones, naked and as well with phone covers. But even if you take the cover off with some of the lenses (the fish eye only I think) you will have a black round frame around the pictures as the glass part would have to be bigger in diameter.
But it still looks cool and the quality is really good (aluminium is very nice and as well the glass is superior quality.) But I wouldn't spend more than the 2.7 USD on aliexpress. It might take some time till it arrives though.
The macro lense makes good pics too. You can see the structure of paper and how well letters are printed on it.
Look for "universal 3 in 1 clip-on lens camera" on aliexpress or ebay.