Marco.org

I often get asked about supporting chapter marks in podcasts. After consideration and research, I’ve decided not to support them in Overcast for the foreseeable future.

The least important reason is that it would be a nontrivial amount of work. There isn’t just one standard: to please most people requesting it, I’d need to support Apple’s original (and undocumented) Enhanced AAC, MP3 Chapters, and Podlove Simple Chapters, all of which are very different. All of them would need to be coded from scratch with low-level file-parsing code, since there aren’t any existing libraries I know of on iOS, and none of them except Podlove Simple Chapters could work on Overcast’s web player.

A bigger problem is the additional UI and control complexity required for navigation between chapters. I already need to account for two “seek” actions in each direction — seek by n seconds, and go to previous/next episode — and that’s already uncomfortably and imperfectly crammed into the limited capabilities of most off-screen control interfaces, including car controls, Bluetooth devices, headphone clickers, CarPlay, and Control Center.

These systems are all designed with, at most, the same 2–4 seek controls that CD players have: previous track, next track, and sometimes, continuous rewind and fast-forward. We’re able to map our four actions onto them, although the difference from their traditional roles still confuses some users.

Chapter support would require adding a third action for each direction (go to previous/next chapter) for six total seek actions, which would even further complicate the control systems and interface. Since none of them support more than four seek actions, I’d need to add obscure gestures or clunky preferences to optionally substitute these actions into the current schemes. And since most podcasts don’t include chapter marks, those gestures would either be disabled most of the time or would confusingly fall back to a different behavior. It’s not impossible to do this, but it’s probably impossible to do it well.

A few podcast apps support chapters and accept this complexity, but many of Overcast’s customers chose it specifically because it has fewer options and simpler controls. Increasing the control complexity may cause Overcast to lose too many fans.

None of those are the biggest reason. I could get over all of those costs if there was strong enough supply or demand. But there’s neither.

The vast majority of chapter-support requests come from a very small, very persistent group. (And I like them. But there simply aren’t very many of them.) Most listeners, by far, don’t seem to demand them, possibly due to the awkwardness of using them in many listening contexts.

The supply side is even worse. They place a big enough burden on podcast producers — especially since Apple removed all support for their creation from GarageBand — that it’s simply not worth including them for the tiny portion of listeners who request them. Making podcasts already has too many steps and takes too much time, and the last thing producers need is another manual, time-consuming step, especially one that their editing tool of choice most likely doesn’t support.

Some have argued that not supporting chapters in Overcast is itself restricting supply and demand, but Overcast simply isn’t that powerful — it has only been out for 6 months, and podcast chapters failed to gain traction for almost a decade before that.

So for now, chapter support simply isn’t worth its costs. If supply or demand substantially change in the future, I’ll gladly reconsider.