https://play.google.com/store/apps/details?id=net.osmand.telegram
Maybe one day someone writes it for matrix? In the meantime telegram is good enough.
Locus is the new cool kid on the market https://apt.izzysoft.de/fdroid/index/apk/app.myzel394.locus I have no idea how trustworthy it is but it looks promising.
I don’t think that they published it as a response to the angry users. We wern’t that loud and signal had a reason to do so. That was when they worked on the cryptocurrency and the spam protection. In signals case it dosn’t matter much if the server is compromised since the important part happens on the client side. The server can only forward encrypted salad or not deliver a message. Or log the meta data of the messages. E2e will always be there, despite the server being compromised.
Who? (That blog post is a couple of years old amyway)
That hasn’t been the case in the past two years and I doubt it has ever been.
Then don’t bring it up.
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Matrix is not only a viable alternative to discord but to all other messaging services. Nothing keeps you from replacing whatsapp with it. However matrix does produce lots of metadata and your server has access to it. If you don’t like your admin to have that metadata then only a p2p service is an alternative. Signal doesn’t store the metadata forever on their servers. Everything else is encrypted.