Wow. So, the magnetic field doesn't mess with the electronics of the phone?
Also people significantly overestimate the amount of current a normal (something you’re gonna encounter in day-to-day life) magnetic field can induce in a wire. There’s a good reason motors are packed with so many windings, you either need an incredibly large magnetic field, or a crap ton of wire, to get an interesting amount of current.
Magnetic fields can saturate ferrites and affect coils, but the slight deviations in few components should be nothing the closed loop circuitry won't handle. You'd need a stronger/closer magnet for that.
Solid state circuits usually have tiny sensitivity to static magnetic fields as opposed to EM waves, which they need to handle gracefully.