Description of App
App Store description: Currently only available in English and Italian! A voice aloud reader, completely offline on your device. No internet required, no limits, no subscriptions. Just listen to that long wall of text that you really need to read or save it for later, with the voice you want. What is Koro about: TEXT TO SPEECH: - Unlimited speech synthesis: turn text of any length into spoken language, whenever you need. Simulate interesting podcasts or relaxing audiobook. - Mix and match voices: choose from built-in voices or blend them together to create your own unique sound. Make it sound just right for you. - Text import: drop in text files or PDFs and Koro will read them out loud. Great for articles, documents, or anything you want to listen to. - Share your audio: save speeches as audio files and share them anywhere. Listen back anytime, even without the app. - Advanced Customization: if some words don’t sound right, add their pronunciation at phoneme level for a perfect speech. TRANSCRIPTION (English): - Live transcription with Whisper. - Extract speech from video and audio files. SUMMARIZATION: - Summarize text with a local language model. - Long text summarization and rewriting. Privacy first: Everything happens right on your device. No cloud services, no data usage, no restrictions. Since everything works offline, your text never leaves your phone. Complete privacy. Performance: The speed and general performances of Koro change depending on your device model. Supported languages: English (American and British) and Italian. Transcription is supported in English. For questions: [email protected]
Comments
Can you use the voices outside the app?
Can the voices be used as VoiceOver or system voices?
Apple system voices
Hello, as far as I know, Apple still doesn’t allow third-party TTS to be used as the system TTS for VoiceOver. When it comes to using the voices outside the app, the only option is to export the audio file generated within the app.
nah, you can get 3rd party voices.
They do though. there's an api and everything I think. espeak is a great example, I have personal experience given I use it as my daily driver.
Espeak
I’m not a developer myself, but I already thought about eSpeak when this question came up. It does seem like it’s the only third-party voice that actually made its way to the iPhone as a system voice, so there must be a particular reason for that. Plus, the voices aren’t AI or natural sounding, they’re still the old robotic style.
From what I understand, Apple doesn’t let third-party voices hook directly into VoiceOver the way Android does. They keep everything closed off, so you can’t just install something like a cappella TTS and set it as your system voice. eSpeak is more of a special case—it’s open source, really lightweight, and easy to compile across platforms, so developers managed to make it run inside iOS. It doesn’t need licensing or fancy processing, which probably made it simpler to get through Apple’s restrictions.
Other companies don’t bother because Apple hasn’t given a proper framework for outside voices to work as system TTS. Apple prefers to keep full control of the voices we get on iOS, like Siri voices or their downloadable premium v vocalizer voices. That’s why eSpeak slipped in as the odd exception, while everything else stays locked out.
Tts reader
And the app I’m recommending here isn’t meant to be an alternative to VoiceOver. It’s more of an alternative to TTS readers like 11 Reader or Speechify, since its purpose is reading text, not functioning as a screen reader.
Please admit you're wrong when you are in fact wrong.
cerprog or however you spell their name does... Nothing requires licensing or special processing, if you have a lisence to use them in an app... unless explisitly stated you can use them as system voices, assuming you go through that effort. Apple allowes 3rd party voices, it has since Ios16, the's a framework and everything. No alternatives to voiceoover exist because of apple's ristrictions, but there's no reason the developer can't make them usable by the system, please don't rely on chatgpt to fill out holes in your arguement unless you know what your talking about, it reflects poorly on you if it makes mistakes, which it just did, several of them in fact.
contact developers
How can I contact the devs behind Korovoice? The email adress on theiol website does not work.
Contact developers
Yeah I also got a notification from Gmail this morning when I replied to the developer’s email saying the address isn’t available. Their website has a link to their Threads account, but if I find another way to contact them, I’ll let you know.
tts
Nobody's claiming it's a sure thing, but if it were really possible to get more third-party voices on iOS, we’d probably already see a lot more than just eSpeak. Apple might have opened up the tools for it, but so far, you don't really see any mainstream voices showing up as options for VoiceOver. It might be possible in theory, but it doesn't seem like developers are actually doing it. And if there's another TTS apps that can do the same thing, then great!
No, straight up no, not even mildly correct.
Apple has a formal interface for custom TTS engines on iOS, iPadOS, and macOS. Developers build an
AVSpeechSynthesisProviderAudioUnitand expose voices that the system can use, which Apple introduced and explained in the WWDC23 session “Extend Speech Synthesis with personal and custom voices.”This isn’t theoretical. eSpeak-NG ships on the App Store with a compatibility layer so its voices appear for VoiceOver, which AppleVis documents on its app page and in TestFlight discussions showing the voices inside VoiceOver settings.
RHVoice is also available and marketed for use “with VoiceOver… or any other app that can use a text-to-speech engine,” with setup notes and unsupported-language guidance on the developer’s iOS pages and iOS support notes.
Personal Voice and Live Speech are different features. Personal Voice is created for AAC scenarios and is selected within Live Speech; Apple’s own guides show how to create Personal Voice and how to use it in Live Speech and on Apple Watch. None of those flows register a third-party, system-wide TTS engine. That’s what the provider audio unit is for.
Koro today is an offline text reader with English and Italian voices and audio export. That scope is clear on the App Store listing. If the developer adds a Speech Synthesis Provider Audio Unit and registers their voices, those same voices can appear in Settings for VoiceOver and Spoken Content like eSpeak-NG and RHVoice. Apple’s provider docs are here:
AVSpeechSynthesisProviderAudioUnit