For anyone trying the update, the SampleApp needs a change to the code in the renderer as it defaults to SH0. The app on App Store has not been updated in ~a year, so you won’t see it there either yet. Looks amazing when you see SH3 on device!
MetalSplatter for Apple Vision Pro released V1.0 adding spherical harmonics (SH 0-3), SPZ support, and visionOS 26 support.
MetalSplatter remains free and MIT Licensed for gaussian splatting!