[GauntletWizard]

A similar anti-pattern - WhatsApp has it's own contact list and list of users. However, you can't use it without granting the Contacts permissions. On my phone, though I have WhatsApp installed, I can't create a new chat - It just brings up the "Enable Contacts" dialogue. I can however use their web-client to initiate a chat, and when people can message me I can respond.

[agile-gift0262]

you can also start a conversation going to the URL wa.me/<phone number> in a browser