I can't think of any ferrous parts in a modern phone. Enclosures are all either plastic, aluminum or magnesium. Circuit board will be copper. Maybe some intern

I can't think of any ferrous parts in a modern phone. Enclosures are all either plastic, aluminum or magnesium. Circuit board will be copper. Maybe some internal structural elements or RF shield cans are made of steel? Microphones are MEMS these days, so no magnets there. Speaker magnets are tiny and also tend to have weird magnetization patterns that seem useless for making a compass (e.g. disc with a circular channel for the coil where N-S are inside of the channel)