Catching an iPhone mugger without iCloud

Last week I got mugged, and lost my iPhone as a result. iCloud was not enabled, so "find my iPhone" wouldn't work (phone's GPS was water damaged anyway; it'd always think I was in Union Square even though that's not where it got water damaged).

I called my provider to add the phone to the stolen registry, disable calling, all the usual stuff.

To my surprise, a group text a friend of mine sent out got a response; apparently iMessage was still working and the genius in possession of the phone decided to respond to the group text with a "who's this".

I'm thinking of having someone else send an iMessage with a hyperlink, and attaching a script to get their IP (since they must be connecting via wi-fi) and send it to the authorities. Normally I'd consider it unlikely to work but this person has already shown they're not the sharpest knife in the drawer.

My question is: if you were in unlawful possession of somebody else's iPhone and not bright enough to wipe the device or get rid of it, what's an example of a text message you would be most likely to tap a hyperlink through?