Xbox Insiders in the Alpha Skip-Ahead ring can now test the latest system update which includes an integrated Twitch live-streaming feature.
Being integrated means you will not need any apps in order to stream using the service.
To stream using Twitch, navigate to the “Capture and Share” tab and choose “Live streaming”. Here you will need to link your Twitch account using a mobile device or using console Settings. Once the account is linked, hit the “Go live now” button to start streaming gameplay to Twitch. This feature only streams gameplay, so viewers will see a pause screen if you navigate to home or another app.