The old Twitch app is not working anymore, if you try to run it. You will receive a message saying that this version was shut down and you will need to update.
So head to Google Play and install the new Twitch app.
The old version will remain on your device and will be different than the new one.
You can easily distinguish the versions since the new application has a white icon, instead of the old purple.
So in the new app, there is a new option to watch vods. From what I’ve noticed, the Vods have sound, they are not muted like they are on the PC, at least some of them, the streams who run copyrighted music.
Before this Twitch app version, users could watch Vods with another app called TD. More information here.