>> If you're arrested in California, even for a traffic stop,
>> police can rifle through the old text messages, photos, ...
>
>
> [WS:] Is not it the so-called "implied consent" principle?
No, it's valid for any lawful arrest; the example of a traffic stop isn't really germane.
If you're walking down the street and are arrested, your phone is now fair game, just like anything else in your pockets or in your wallet.
/jordan