InDesign. I've self published books that major publishers have purchased the rights to. They'll generally require the Indesign (package) as part of the contract. I haven't heard of publishers using any other software.

@Tikiri Herath That said, this is a self publishing community, which I also still do on occasion, so I think in a self publishing situation refining a nitch should probably be done with additional titles, which is MUCH harder and MUCH slower in traditional publishing.

50 / 50 I have a ten book series with Chris Ferrie coming out next year with Penguin, but I need to do more self publishing because it is just so much more profitable. I have 3 flagship titles I'll probably self publish this year. One is already through prepress with the printer.I have a second 10 book series I'm about halfway through that I'll like to traditionally publish. I'd be happy to talk about it, and learn from you (it looks like you've been very successful in this regard), during a future coffee chat.

I like mornings, and I'll be there. I'm a full-time author with three kids, so mornings work best (after I've written my "THOU" (first 1000 words of the day) of course :-)

I'm on the call now, but I'm the only one...

Not using Indesign. Back in 2019, I used a word file to re-upload a book that was selling about 100 copies per day. It got through KDP’s print checks without issues, but instead of text, when it shipped to the consumer, it was, honest to god, SHAPES. Everywhere. And anywhere where there was a text box, the paperback had giant triangles and other odd shapes. Turned out the conversion from Word to PDF was corrupt and there were no actual humans in KDP’s quality control loop to catch it. Amazon shipped thousands of misprinted copies before I figured it out. One star reviews flowed in for MONTHS. People started posting images of the interior, with shapes instead of text. The worst part is that Amazon wouldn’t remove the reviews for the misprints. We moved the book over to Indesign, exported a clean file, and this fixed the issue. Fortunately, reviews with actual images of the interior took the place of the misprint images and sales eventually returned to normal.

@Danielle Marietta I spend about $30k per year on Amazon ads. If the ROI is positive, you might as well spend as much as you can.

Hello! I write astronomy nonfiction and YA science fiction. Working on moving my nonfiction from traditional publishing (Penguin) to Amazon Advantage.