Switched to Pixave after Ember became abandonware.

Is pdf rendering (for iOS assets) also using Core Graphics?

I just found out that if you export your graph as .pdf from the Grapher.app and open the path in Ai, you can the “stitch” back those paths with the Join command ⌘+J and use the Simplify command from Object → Path → Simplify, with max out curve precision slider to 100% will produce a pretty nice and hopefully accurate curve. Here’s my example:

The outer path was simplified and the rest are the original paths.