Comparison

Bulb vs CHSK

Price, ratings, monetisation and update history for both apps, side by side โ€” 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

CHSK

Prepare for HSK Chinese proficiency tests from levels 1 to 6 with mock exams, targeted practice modules, and vocabulary flashcards. Engage in word matching games and access a comprehensive grammar list with search functionality.

Highlights
  • Mock HSK exams with timer
  • Targeted listening, reading, writing practice
  • Bilingual vocabulary flashcards
  • Timed word matching game
  • Grammar points index and search
Features
Read full description

CHSK is a preparation app for the HSK exam, levels 1 to 6. -Mock exams Complete past papers with a 90-minute timer. Listening, reading and writing appear in the order used in the exam. -Targeted practice Practise listening, reading or writing on their own, sorted by level and question type. -Daily Words Vocabulary flashcards in both directions, Chinese to English and English to Chinese. -Word Match Match 20 Chinese words to their meanings against a timer. -Grammar list Grammar points for HSK 1 to 6, with an index and search.

Screenshots

CHSK4 screens

Verdict

The call

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

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

CostPrice ยท In-app purchases ยท Ads ยท Monetization

Both are free to download. Bulb sells 3 in-app purchases, starting at $2.99 per 7 days. CHSK asks for nothing beyond the download.

UpkeepUpdate frequency

Bulb ships an update every 5 days, CHSK every 3 days. The most recent releases landed on October 15, 2026 and October 25, 2026 respectively.

Scorecard1 real difference ยท 7 level
Bulb versus CHSK: the parameters behind the verdict, then further details
ParameterBulbCHSK
PriceFreeFree
Positive reviewsโ€”100.0% of reviews
Update frequencyEvery 5 daysEvery 3 days โ€” better
AdsNoNo
In-app purchasesYesNo โ€” better
Monetizationโ€”Free
DevicesiPhone, iPad โ€” betteriPhone
Requires iOS17.017.0
Further details โ€” not scored
Size40 MB102 MB
Age rating17+9+
DeveloperDanis GaiazovWuxi Wudao Matrix Information Technology Co., Ltd

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
None

CHSK

No in-app purchases

Questions

Is Bulb free?
Bulb is free to download, with in-app purchases available.
Is CHSK free?
CHSK is free to download, with no in-app purchases.
Do Bulb or CHSK have ads?
Neither Bulb nor CHSK shows ads.
Which is updated more often, Bulb or CHSK?
Bulb ships an update every 5 days, and CHSK every 3 days. Most recently, Bulb was updated on October 15, 2026 and CHSK on October 25, 2026.

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