Depends on local laws, but if the cops ability to seize your property without warrant isn’t protected by local laws:

Ask if they have a warrant and if they don’t then take your phone oout and power it down, then put it back in your pocket and tell them they can direct complaints to your lawyer because you’re not handing over any devices.

If they seize it without a warrant then you can sue the department, although if they have reasonable suspicion then you won’t have much luck.