MacSparky reviews the Moment Lenses:
Moment makes some really nice third-party glass to give you more options when you take photos with your iPhone. They have an assortment of lenses ranging from zoom to macro, and they all use a clever screw-on mechanism that lets you attach your lenses onto a special iPhone case made by Moment with mounting points. I have really come to enjoy these lenses and want to share some of the details.
And just like that, I jump from deciding between a Fujifilm X70 or X100T to which Moment case to get. Damn you Macsparky.