A useful case protects the parts most likely to meet a hard surface without making the phone awkward to use. Check that it is designed for your exact model, since camera cutouts, buttons, and charging ports can differ even between similar devices. A raised edge around the screen and camera may help prevent direct contact when the phone rests face down or lands on a flat surface.
Think about your everyday risks. A slim case may suit careful indoor use, while a grippier or more substantial design may be preferable for work outdoors or frequent travel. Consider texture, weight, pocketability, button feel, and access to wireless charging or accessories. A bulky case is not automatically protective, so look for clear design details and independent testing when available. Check whether screen protectors fit without lifting at the edges.
Cases can collect dust and trap grit, which may scratch a phone over time. Remove the case occasionally and clean both surfaces with a suitable soft cloth, following care guidance for the materials. Replace a case if it is cracked, stretched, or no longer fits securely. Even a protective case cannot guarantee that a phone will survive every drop, so pair it with careful handling and a screen protector if that suits your needs.