@juergen
Android is the primary platform for now, but an iOS version is planned. Distribution will likely go through AltStore, as mainstream app stores may flag apps with embedded servers.
Regarding multi-device access, Holos follows a "one device, one instance" philosophy. Your phone is your server, with your keys and data living locally. This is what gives you true ownership. Multi-device sync isn't currently supported but is being considered for the future.