Just leave your phone at home and bring a plain old small digital camera, agree ahead of time with friends on when and where to meet up. It's interesting to me and i guess showing my age that this isn't self evident to everyone everywhere.

I suspect the old school stuff is generally less monitored. I think some of the cheap Baofeng radios support AES256 encryption. I think that's technically only legal with a business license from the FCC or some such, but I'd be a lot less worried about an FCC fine than having my phone tracked. There's probably some quick keypresses to clear the encryption config so it looks like it was on plaintext.