Rav Sha'ul

Whats’ app, while E2EE can still pull lots of information from who you message, how often, the size of the messages, and contact’s phone number. Messenger has the content of your messages and with whom you converse according to Facebook account info stored on Facebook servers. Snapchat has a record of all activity, contacts, and message content. The messages only disappear from app but not from SnapChat servers. All 3 of those record of how you live your life, except Whatsapp can’t see content of messages but still has your activities and contact phone numbers.

Signal was ordered to turn over user content to court and Signal only had when the user last connected to the service and date of account creation. Signal had zero information about messages, when messages were sent, or to whom.

I don’t use Matrix due to a permanent copy of all activity being kept on servers. It seems Matrix only has private group chats but not end-to-end direct messaging to add a contact and message them, you have to invite a user to a chat.

I will second the others that only suggest Signal or a variant of Signal like Langis or Molly. Everybody has each other’s phone numbers, go with Signal so people don’t need any other contact information.

For which ROM to use, I believe any ROM based on AOSP will suffice because even that will fully eliminate all Google tracking, I think LineageOS is the worst one. I do recommend Pixel since you can lock the bootloader after flashing it. You could try CalyxOS.

For privacy, I only use phone for communication, I don’t use cell data service so no internet when I’m outside, no messaging, until I connect to wi-fi again. In F-Droid I turn off all anti-features in settings, and everything I install is from F-Droid. No social media and no Aurora store to use Play Store

I have never heard of Bastyon before. I have an account on there. It would be helpful if it had a libre app to use.