If you use the Podcasts app to listen and watch podcasts, you can also create custom stations that'll filter in podcasts based on which subscriptions you add to that section. You can think of stations as nothing more than creating playlists just like you do in the Music app.
Launch the Podcasts app from the Home screen of your iPhone or iPad.
Tap on the My Stations tab along the bottom of the screen.
Now tap on the New Station button.
Name your station and then tap Save.
You'll now be taken to a screen where you can add from your current subscriptions to that station. Once you're done, just tap the blue Done button in the upper right hand corner.
That's all there is to it. Notice you'll have to be subscribed to podcasts in order to create stations, so make sure you do that first before you attempt to create custom stations.