Flash Season Zero Chapter 8 is out digitally, completing the story of Mr. Bliss and his circus. They’ve previously said that this story takes place between episodes 1 and 2 of the TV show, but there are a few cues suggesting that it takes place after episode 2.
DC has also added two more Silver-Age issues to its digital backlist: Flash #114-115 (1960), featuring the return of Captain Cold, Kid Flash vs. the King of the Beatniks, the Elongated Man, and the Day the Flash Weighed 1,000 Pounds.
You can read these at ComiXology, Google Play, iBooks and in theory Comics Plus (though they need to work on their search feature — searching for “Flash” should not bring up several pages of American Flagg first!)