It was a radical idea handed over to Chancellor Merkel's Berlin crowd....from the Hessen Chief (Bouffier, CDU) over handling migrants or immigrants who don't want to identify themselves or their country of origin.
The idea? Once you show up and apparently play this game with the BAMF Agency.....they confiscate your smart-phone (on the spot). They will use it to track down who you chat with and eventually figure out your status.
Trying to hide the phone? I'm guessing that they'd send the cops around to you everyday and play the game out....eventually getting your phone.
Getting a replacement phone? That's the thing....you'd probably find some kid who'd sell you another phone for 50 Euro and just continue on, and find a week or two later....the cops coming around to possibly confiscate that phone.
This is one of the odd characteristics I've come to notice over the past four years....virtually every single immigrant/refugee/asylum requester.....has a smart-phone.