Syllabbles Reviews

I have a great deal of experience with AI ebook production platforms. I purchased Tier-1 even though important features are left out of Tier-1 and Tier-2. The inclusion of BYOK support in Tier-1 is clearly stated. That statement alone inspired me to purchase as I am aware that different AI models produce dramatically different results - something I would like to control and experiment with. BYOK would allow that - or so I thought.

I'm going to state this very clearly - BYOK IS NOT supported in Tier-1. The following is word-for-word from Syllabbles Support today: "...Tier 1 does not include AI model selection. Even though you added your Claude API key, you won’t be able to choose it in the eBook AI Writer on this tier. To use Claude or select models, you would need a higher tier."

I thought Syllabbles would be worth the Tier-1 investment if I could use my own API key, my own prompting, and then take advantage of the seemingly advanced built-in design features. The promise of Elevenlabs via API key was also attractive.

Look at the length of time and number of purchases I've made on AppSumo - in all those miles I've never made it a practice to negatively review a product. But gentlemen, what appears to be a decent product is seriously (best case scenario) miscommunicated.

***EDIT: How is BYOK supported - in detail?

Hi Magnus and Team,

I must admit I am quite impressed with this Swiss Army knife concept of an AI App tool targeted to do and accomplish many things for AI Audio and book publishing content makers. Just after I subscribed to Tier1 and tried things out with hope of possibly uprading to Tier 3, I started on the Podcast option which I find quite exciting. I was particularly very interested with the possibility of generating a 3 or 4 speakers podcast episode and was quite impressed with what i can create with it.
Though the languages offered are few yet it offers a wide array of creating possibilities that simply justified further investment and upgrade in subscription Tier.
Please try and add more popular languages and voices to help appeal to a wider audience of innovative content makers helping them deliver great podcast and other Ai book cum ebook format publishing services. From every continent of the world, you can aim to add more major language and voices.
Anyway for such detailed offering so far with great concept and identified gap/niche you tried to fill, I give you 10 tacos.
More grease to your elbows.

I had high hopes for this tool, but my experience so far has been disappointing. My primary reason for upgrading to Tier 3 was the Podcast feature, and unfortunately it hasn't met expectations.

The AI voices need significant improvement. They sound robotic and are heavily accented toward Indian English, which doesn't suit the content I'm creating. Here are my top suggestions:

1. Add more American English voice options across different age ranges (young, middle-aged, and mature) with varied tones, including deeper voices for a more natural, professional sound.

2. Add playback speed controls for speakers. Currently there's no way to adjust the pace, and the podcast output sounds rushed and unnatural.

I haven't tested the eBook feature yet, but I'll follow up with feedback once I do.

Where do I start? I bought this product for the sole reason of creating ebooks but I got more than I bargained for. I can create ebooks, audiobooks, flipbooks, etc and get them published.
I also was able to get some AI features in there which was a beautiful surprise for me. But my best highlight is that I can customize almost everything about my books. This is another greeat purchase from Appsumo.

The app is well organized and logically built, which makes it easy to find features and create what you want. The main drawback I found is the voice quality — they don't sound good enough for podcasts or audiobooks. I understand this is early-stage: I even tried to use my own OpenAI API for voices, but that API currently generates text only, not audio.

I wanted to leave a positive review to help the developers. I know they can't include every feature from the start. They offer a strong selection of LLMs on tier 3, which is useful but sometimes confusing because not every model suits every task, so you need to try several to find the best fit. Overall, they’ve done a great job and the app has real potential, I hope the quality of the audio voices will improve with time or at least they will allow us to use audio voices from open ai with our own API keys.