Question about Celeste’s phone/ what did david do with it

Hi,
Just a random question that came across my mind. We know that David and Celeste texted the night she was murdered, as well as when she was in the uber, and David sending texts to her phone after her murdered her. So we know that David had possession of her phone from that night. Do you think that he discarded her phone along with her passport card and other personal belongings? Or that he just destroyed it? What are your opinions etc?