This filter clip is interesting in that you can unscrew the filter entirely and use any 52mm filter. I think I have a glass solar filter that I can change in this size. The clip is super easy, holds securely, and doesn't seem to put too much pressure on the screen side.

It's also possible to rotate the filter for different polarization. The images I attached are of late afternoon sun on some black shiny weed fabric on the ground, with the polarizer rotated so it maximally excludes reflection. You can see how different they are. The subtle vertical light artifacts are from my own double-paned window, because I took the photo through a window in sun--they're not from the filter. You can see the difference it makes. The rest of the landscape had a slightly warmer cast, but otherwise, was very similar filtered and non-filtered. I'm impressed. This filter works well without excluding too much light, which some polarizers do.

My only concern is a strong rubber smell, which is probably the piece that protects the screen from getting scratched by the clip--I hope it's a durable part. And I wish the case for the filter were more portable for on-the-go use. For the price, though, it's a great neutral density polarized filter for phone photography.