An overview of all talks can be found here: https://fahrplan.events.ccc.de/congress/2018/Fahrplan/

VoDs of past talks are already being uploaded here: https://media.ccc.de/c/35c3

There is also a free iOS app with the whole schedule and live streaming included https://itunes.apple.com/de/app/congress-35c3/id941205524

Android version here (although I don't know about streaming in this one): https://play.google.com/store/apps/details?id=info.metadude....