Comparison

Folio vs Vox9 Audiobooks

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

Folio

Features
Read full description

Folio gets you to actually finish an English classic — in the original, cover to cover. Most reading apps drop you into a hard text and hope you cope. Folio is different: it's a prep course, not just a reader. Before you read, you pre-study the ~600 words that cover 95% of that specific book — plus its key grammar, idioms, and character names — using spaced repetition with self-rated confidence. Once your "reading power" is high enough, you read the unabridged original with a tap-to-translate dictionary and LibriVox audiobook narration. HOW IT WORKS 1. Pre-study the book. Spaced-repetition flashcards for the vocabulary, grammar, idioms, and names that unlock the text — chapter by chapter. Folio catches the words you only think you know. 2. Watch your reading power rise. A per-chapter gauge fills as you study, rewarding real recall. 3. Read the original. The full, unabridged text with tap-to-translate and audio. Finish it and earn a completion card. IN YOUR LANGUAGE The texts stay in English. Definitions, notes, and example translations appear in your language: Japanese, Simplified Chinese, Spanish, Korean, Brazilian Portuguese, or French. THE LIBRARY A growing library of public-domain classics — start free with Alice's Adventures in Wonderland, then unlock the full collection. HONEST BY DESIGN - No account, no sign-in. Everything is stored on your device. - No ads, no tracking. - Book texts from Project Gutenberg and Standard Ebooks; narration from LibriVox — all public domain. Start free, and read your first classic to the very last page. Terms of Use (EULA): https://readfolio.co/terms Privacy Policy: https://readfolio.co/privacy

About

Vox9 Audiobooks

Discover and listen to serialized fiction narrated by AI voices. Explore thousands of stories across various genres, with options for offline playback and customizable listening speeds. Enjoy unique features like scene images and captions.

Highlights
  • AI-narrated serialized fiction
  • Offline episode downloads
  • Customizable playback speed
  • Background and lock-screen playback
  • Genre browsing
  • Scene images for supported episodes
Features
Read full description

Vox9 is a streaming app for AI and human-narrated independent fiction - sci-fi, fantasy, HFY, horror and more. Serialised stories from independent authors, released chapter by chapter. Over 1,500 episodes, from quick one-shots to multi-hour epics. LISTEN YOUR WAY • Background and lock-screen playback with full media controls. • Captions on almost every episode - one tap on the player, and your choice is remembered. • Sleep timer, including stop-at-end-of-episode. • Playback speed from 1× to 2×. • Your progress syncs, so you always resume where you stopped. • Subscribers can download episodes to listen offline. FIND YOUR NEXT STORY • Search every series, author and episode. • Browse by genre - sci-fi, fantasy, HFY, horror, creepypasta, romance, crime, comedy. • Curated picks for new listeners, top-rated stories, and trending episodes. • A dedicated section for human-narrated audiobooks. • Follow authors and get notified when their new episodes land. • Finish a series and get suggestions for what to listen to next. MORE THAN AUDIO • Scene images that change as the story unfolds, on supported episodes, with a full-screen view. • Rate episodes and see what other listeners rated highest. ABOUT AI NARRATION Stories on Vox9 are written by independent human authors and narrated using AI voices. A growing selection is narrated by human voice actors and marked as such. Most episodes are free to listen to with occasional short audio ads. Some episodes are only available to author subscribers.

Screenshots

Folio4 screens
Vox9 Audiobooks4 screens

Verdict

The call

The clearest difference is in-app purchases: Vox9 Audiobooks at none against Folio's 3. On price, update cadence, ads and device support there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. Folio sells 3 in-app purchases, starting at $4.99 per month. Vox9 Audiobooks asks for nothing beyond the download.

UpkeepUpdate frequency

Folio ships an update every 9 days, Vox9 Audiobooks every 8 days. The most recent releases landed on November 5, 2026 and November 10, 2026 respectively.

Scorecard1 real difference · 9 level
Folio versus Vox9 Audiobooks: the parameters behind the verdict, then further details
ParameterFolioVox9 Audiobooks
PriceFreeFree
Rating—4.7 (81 ratings) — better
Positive reviews—50.0% of reviews
Number of ratings—81 — better
Update frequencyEvery 9 daysEvery 8 days — better
AdsNoNo
In-app purchasesYesNo — better
Monetization—Free
DevicesiPhoneiPhone
Requires iOS16.0 — better16.4
Further details — not scored
Size10 MB54 MB
Age rating4+17+
DeveloperTetsuhiro Nomuravox9 Studios

In-app purchases

3 purchases

Folio

Subscriptions2
  • Folio — Monthly7 Days trial$4.991 Month
  • Folio — Yearly7 Days trial$29.991 Year
One-time1
  • Lifetime — Full Library$49.99
None

Vox9 Audiobooks

No in-app purchases

Questions

Is Folio free?
Folio is free to download, with in-app purchases available.
Is Vox9 Audiobooks free?
Vox9 Audiobooks is free to download, with no in-app purchases.
Do Folio or Vox9 Audiobooks have ads?
Neither Folio nor Vox9 Audiobooks shows ads.
Which is updated more often, Folio or Vox9 Audiobooks?
Folio ships an update every 9 days, and Vox9 Audiobooks every 8 days. Most recently, Folio was updated on November 5, 2026 and Vox9 Audiobooks on November 10, 2026.

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