Comparison

Bulb vs Once Upon A

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

Head to head
About

Bulb

Read full description

Learn languages by reading real books and browsing websites. Tap any word for instant translation, build vocabulary from what you read, and improve your writing with AI feedback. Bulb is for people who want to learn through authentic content instead of gamified drills. Import EPUB books, browse foreign-language websites with built-in translation, and use AI feedback to improve your writing. === HOW IT WORKS === READ REAL BOOKS Import EPUB books in your target language. Tap any word for instant translation and pronunciation. Save words to your vocabulary as you read. Double-tap sentences for full context. Create bookmarks and highlights. BROWSE AND TRANSLATE WEBSITES Read news, articles, and blogs in your target language with built-in translation. Tap unfamiliar words for definitions. Save vocabulary while browsing. Practice with real-world content that interests you. BUILD VOCABULARY IN CONTEXT Every word you look up is saved with its original sentence. Review with spaced repetition flashcards generated from your reading. Practice translating sentences back and forth. Learn words as they are actually used. GET AI WRITING FEEDBACK Write essays, emails, or journal entries and receive detailed analysis of grammar, style, and vocabulary. See specific error patterns with visual charts. Get suggestions tailored to your level. Track your improvement over time. === WHO IT IS FOR === - Professionals improving business English or foreign-language writing for work - Students preparing for language exams with real reading and writing practice - Book lovers who want to read novels and nonfiction in other languages - Learners who prefer authentic content over artificial lessons and gamified drills === SUPPORTED LANGUAGES === English, Spanish, French, German, Chinese, Japanese, Italian, Portuguese, Russian, Korean, Arabic, Serbian === KEY FEATURES === - EPUB reader with tap-to-translate - Built-in web browser with instant translation - Automatic vocabulary capture with context - Spaced repetition flashcards - AI essay analysis with grammar, style, and vocabulary feedback - Writing progress tracking with visual charts - iCloud sync across all your iOS devices Built for focused reading, vocabulary, and writing practice without gamified drills. Requires internet connection for AI features and translation. Privacy Policy: https://thebulb.app/privacy Terms of Service: https://thebulb.app/terms

About

Once Upon A

This educational app helps users learn Mandarin Chinese vocabulary using narration and images. It supports both PinYin and BoPoMoFo learning methods. The app is designed to reinforce word recognition and pronunciation.

Highlights
  • Mandarin vocabulary learning
  • PinYin support
  • BoPoMoFo support
  • Narration for pronunciation
  • Image-based learning
  • Reinforces vocabulary
Features
Read full description

Learn Mandarin Vocabulary in PinYin and BoPoMoFo! Once Upon A is the first and only app on designed to reinforce Mandarin Chinese vocabulary with narration and images. Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

Screenshots

Once Upon A4 screens

Verdict

The call

The clearest difference is iOS requirement: Once Upon A at 15.1 against Bulb's 17.0. On price, update cadence, ads and in-app purchases 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. Bulb sells 3 in-app purchases, starting at $2.99 per 7 days and Once Upon A sells 14 in-app purchases, starting at $19.99 per month. Whichever you choose, the download price is not the number that matters.

UpkeepUpdate frequency

Bulb ships an update every 5 days, Once Upon A every 3 days. The most recent releases landed on October 15, 2026 and October 20, 2026 respectively.

Scorecard1 real difference · 9 level
Bulb versus Once Upon A: the parameters behind the verdict, then further details
ParameterBulbOnce Upon A
PriceFreeFree
Rating—5.0 (2 ratings) — better
Positive reviews—100.0% of reviews
Number of ratings—2 — better
Update frequencyEvery 5 daysEvery 3 days — better
AdsNoNo
In-app purchasesYesYes
Monetization—Free with in-app purchases
DevicesiPhone, iPadiPhone, iPod
Requires iOS17.015.1 — better
Further details — not scored
Size40 MB71 MB
Age rating17+4+
DeveloperDanis GaiazovSassyTags

In-app purchases

3 purchases

Bulb

Subscriptions3
  • Premium Weekly$2.997 Days
  • Premium Monthly7 Days trial$6.991 Month
  • Premium Annual7 Days trial$49.991 Year
14 purchases

Once Upon A

Subscriptions1
  • Monthly Subscription$19.991 Month
One-time13
  • Small$4.99
  • 3 Story Pack$9.99
  • Medium$9.99
Show 10 more
  • 10 Story Credits$10.00
  • 5 Story Pack$14.99
  • 20 Story Credits$16.00
  • 7 Story Pack$19.99
  • Large$19.99
  • 25 Story Credits$20.00
  • X Large$29.99
  • 50 Story Credits$35.00
  • 75 Story Credits$50.00
  • 100 Story Credits$60.00

Questions

Is Bulb free?
Bulb is free to download, with in-app purchases available.
Is Once Upon A free?
Once Upon A is free to download, with in-app purchases available.
Do Bulb or Once Upon A have ads?
Neither Bulb nor Once Upon A shows ads.
Which is updated more often, Bulb or Once Upon A?
Bulb ships an update every 5 days, and Once Upon A every 3 days. Most recently, Bulb was updated on October 15, 2026 and Once Upon A on October 20, 2026.

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