This looks really promising and the UI is not bad. It is simple to use. The issue - this thing (according to clean my Mac) uses 130% of the CPU on my M4 Air. The heat gets up to 200 degrees. The app then crashes without completing the task. No idea why making an audiobook uses more resources than editing HD video. Seems like a software fail… Find another app to make your audiobooks.

It combined all of my .mp3 files easily enough, but the resultant file was corrupted. It opened in the Mac “Books” app but truncated the last 8 chapters. Even the last chapter title itself was truncated. The Mac Finder correctly shows the total running time of the final file, but Books shows it’s 40 minutes shorter given something in the file told Books there is a hard stop in the middle of Chapter 12 of 20 total chapters. Tried to build the file again several times but got the same result each time. Not worth chasing a refund, though, for so little cash. This app is now in the trash, unfortunately. Bought “Audiobook Builder 2” instead and it flawlessly created a perfect final .M4B file in less than 5 minutes.

I wrote an early review when the app had first been launched in the App Store (which I did not realize at the time.) After finding a way to contact the developer, they responded quickly and positively to my concerns, and updated the app accordingly.

I used this app to combine MP3 files into an M4B audiobook. The exported book would not play in the Books app, but it would play in VLC. Then I converted the MP3 files to M4A, then used this app to merge them into an M4B. This was accepted into Books, but no chapter markers could be found even though one chapter marker per input file was requested.