Session (Signal fork) doesn't require any information. It's end-to-end encrypted by default, and it connects via an onion routing network (LokiNet). And so only LokiNet nodes see the IP address that you connect through. But of course, you connect to them through VPNs or nested VPN chains.
Seems to somehow be associated with the working group for Loki cryptocurrency, but not using blockchain to store messages or message contents, per FAQ.
As I understand it, Session uses LokiNet, and there are also sites, analogous to Tor onion services, and potentially other services. However, running LokiNet nodes requires a substantial stake, which is payable in Loki. The stake is at risk for malicious behavior, and nodes get paid in Loki for services that they provide to the network. Perhaps some features require user payments, but I haven't researched that.
I've looked into a bit more. It uses a crypto based on monero called Loki. Service servers are to be paid out for maintaining the network. It's also possible to mine the crypto. There seem to be software wallet apps available for iOS and Android.
LokiNet reminds me of a self-funding P2P decentralized anonymous analog with massively more functionality to Google Jigsaw[1] project called Outline[2], which runs shadowsocks[3] on Digital Ocean droplets or your own Linux infra.
> TL;DR edition: an onion router with a tun interface for transporting ip packets anonymously between you and the internet and internally inside itself to other users.
> "What if I2P was made in the current year (2018)? What would be different?"
> In short we want to permit both anonymous exit and entry network level traffic between LLARP [aka LokiNet] enabled networks and the internet.
> In short, I want to take the "best parts" from Tor and I2P and make a new protocol suite.
