Asklemmy

But is briar a single, centralized US hosted service?

No. But Briar runs over the Tor network, another project funded by the OTF [0]. Side note, the Tor Project has received $3 million USD from the OTF/CIA, can you trust it when a researcher was able to identify Tor users 100% of the time in a lab experiment and 81% of the time in real-world tests [1][2]?

Does it require you, like signal, to give it info that links to your real identity

Signal never touted anonymity, only privacy. You need to understand your threat model to make an informed decision. Also, if a single researcher was able to de-anonymize Tor users 80% of the time in real life, what chance do you have with a more powerful nation-state, unlimited funds, and ownership of various exit nodes?

Did it close its server source code off for a year?

"Never attribute to malice that which is adequately explained by stupidity" - in this case, we can replace stupidity with a million things that have nothing to do with compromising your privacy, the client is still completely E2EE, open source and has reproducible builds.

Is it possible to download it from f-droid so you can verify its builds are secure

You can download the app directly from Signal [3] or even build it yourself [4] to verify the build in the play store matches the code on github

Does it depend on google or amazon?

If you're using an Android phone, you're likely already depending on Google, although you can still run it on a de-google'd phone. I'm using Signal on a Pixel with stock Android and a OnePlus without any ties to Google using LineageOS, it works great on both phones! It does run on Amazon infrastructure, but again, we've seen Tor is not guaranteeing anyone anonymity anyways.

Does it bundle in a cryptocurrency?

How is this a negative? Some people want this and if you don't want it, don't use it.

Is it possible to verify what the server is running?

The server is basically plumbing/a router. The bulk of the Signal "magic" happens in the E2EE app. Can you verify that your Briar messages aren't hopping through government run Tor bridges/relays/exit nodes?

[0] https://www.opentech.fund/results/supported-projects/tor-project/

[1] https://www.vice.com/en/article/4x3qnj/how-the-nsa-or-anyone-else-can-crack-tors-anonymity

[2] PDF warning: https://mice.cs.columbia.edu/getTechreport.php?techreportID=1545&format=pdf

[3] https://signal.org/android/apk/

[4] https://signal.org/blog/reproducible-android/

EDIT: I do want to add - I'm 100% pro-Briar. It's really easy to attempt to discredit something if you don't understand a threat model, link legit sources, and speak to real flaws, nothing is 100% secure. That said, in today's climate, message privacy is something that Signal can provide with very few compromises in usability.

I'll say it again, I want Briar to succeed and everything I've posted above is just a "devil's advocate" stance to point out that Signal is, today, just as good if not better than most options out there.