My favorite is Flowx[0]. Disclaimer: I'm bias since I'm the developer.

Globally, we have GFS (FV3) and GDPS in the free version, and DWD ICON in pro.

For north America, we have NAM 12km, NAM 3km, HRRR, RDPS, HRDPS in Pro

For Europe, we have DWD ICON EU, DWD COSMO-D2, ARPEGE, AROME and HIRLAM in Pro.

If you double-tapping of a graph, you can compare the forecasts quite easily.

Sorry there is no iOS or web version, nor ECMWF (it's too costly).

[0] https://flowx.io