You can get an idea of the podcast clients that support MP3 chapter markers using this spreadsheet (you'll want column W). Please note it's not entirely up-to-date, with MP3 chapter markers quickly gaining adoption across the spectrum of podcast clients.
Podcast Chapters uses ID3 v2.3 throughout, even if the file that's imported uses a different ID3 tag (or doesn't have one at all).
As of Podcast Chapters 1.2, you can now set the following non-chapter metadata in your podcasts:
As of Podcast Chapters 1.2, you can now add individual chapter artwork. In compatible podcast clients, this will show up as the show art during the time period of the chapter.
Podcast Chapters 1.2 supports importing chapter markers from
cue files. You can import markers using the menu, by selecting 'Import Chapters...' from the 'Chapter' menu, and selecting a
cue files only support importing the title and the timestamp of a chapter, and if you want to add a URL or an image to the chapter, you will need to do that manually in Podcast Chapters.
Podcast Chapters was created and developed by Thomas Pritchard from 2016 to March 2019, when he handed charge of the app over to Fredrik Björeman. I (hello!) have lent a hand with the last few releases, and I look forward to keep things going in very much the same style as before. You can read a bit more over here, if you like.
First of all, that's not a question, it's a statement.
The best place to ask a question is on Twitter (@bjoreman), my DMs are open.