Filter isn't shown in "tracks" on the iphone remote app

when i select “tracks” on my iphone - the filter key is missing. so it’s difficult to search for a track

Is your iPhone up to date with the same roon release as your core?

i don’t know, i downloaded the last app-version. My core is “Version 1.0 (build 227) stable”. can i synchronise the versions somehow?

That’s your player version.
If you go to roon, settings, about and look for the roon versions there it will say roon 1.8 vXXX.
Make sure the version in core and remote are the same and reboot the core as well.

on all devices and on core is the same version: 831. on ipad the filter in track is shown, only on all iphones it doesn‘t work