Get 2 or more of your devices together and connected to your local WiFi, Hotspot or internet. Then simply pair them via QR code and create a new vault. You can then send funds in.
All assets supported by Trust Wallet Core are supported in Vultisig.
Vultisig is audited, open-source and uses a very well-proven TSS library.
Vultisig only charges a flat fee on swap and bridging. There are no other hidden fees.
You can back-up your vault by exporting the vault shares.
No, there are no registration requirements.