When you're close to someone you can make an initial exchange via QR+bluetooth. When you're distant you need to exchange your briar:// links on a different channel.

It's also safe to post your briar:// link online (https://code.briarproject.org/briar/briar/-/wikis/FAQ#is-it-...)

So if anyone wants to try the app but doesn't want to convince somebody else to do so too, just add my link and post yours below:

briar://acyeao3gd3sqldlljx6etcjyxdr4ux6m6s3ge3r4z6st7ju2ac5xg

Using Tor onion services that get exchanges when adding a contact nearby via WiFi or Bluetooth. If adding over the internet, a rendezvous service will be created.