75 text-to-speech voices in 27 languages are available natively on macOS. You might be familiar with some of them, such as Samantha and Alex in US English. Some are not available on iOS and are very good, such as Ava and Tom. Just like iOS, to get the best quality, you need to download “Enhanced” version of these voices. On the Mac this takes a lot of clicks. You need to open Accessibility in System Preferences and select “Spoken Content”. Then, click on the “System Voice” pull-down and select “Customize…”. You’ll see a list of all system voices. If a voice does not have a check-mark next to it, it’s still available but lower in quality. If you check it, an enhanced version will be queued for download. Keep in mind that Siri voices are not available to third party applications.
Third party voices from Acapela, Ivona and NeoSpeech are not available on macOS. We’re working with Acapela now to make them available. Ivona and NeoSpeech voices do not run on Macs so they won’t be available at all.
Some sources are not available on macOS. Instapaper and Pocket are not available yet but will be in a future update. Evernote will not be available at all because Evernote does not support third party app access on macOS.
Supported File Types
Reader for macOS does not support loading of Word, PowerPoint and RTF files. But if you load these files on Reader for iOS, on the Mac you’ll be able to see the Plain Text view of these documents. We’ll try to address this in a future update but it’s a fairly heavy lift.
Safari Extension on macOS works better than on iOS: the PDF output faithfully renders the webpage, while on iOS the layout maybe off.