I think the phone story will be interesting when it's told. Because it couldn't be both left at the scene on her body, as has been stated, and traveling around with the perp, yet found by LE.
I asked about warrants because another case was mired down in debates over pinging vs other location data. The father had reviewed the victim's activity online, and the police, after obtaining a warrant had obtained ping data. At trial, an expert hired by police to further track the victim's movements, showed the entire journey that the victim's phone took to not only the restaurant she drove to, and not only the parking lot she was in, but the space by the dumpster where she parked, the direction she turned in to leave the parking lot, etc., all the way back to her condo parking space, distinguishing that from her, or at least her phone, going inside the condo. Families can't get that kind of info from an app or provider feature, so I really wonder where that phone was when the grandfather tracked it, and at what point on the timeline relative to the murder. Not because I don't believe the family, but because we seem to have a phone with the victim and at another location.