Comparison

BookLight vs ReadGem

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

Head to head
About

BookLight

This app helps language learners build vocabulary by translating words with a single tap while reading EPUB, PDF, or TXT files. It automatically saves new words and uses spaced repetition flashcards to aid memorization, eliminating the need for manual flashcard creation or app switching.

Highlights
  • Tap to translate words instantly
  • Automatic vocabulary saving
  • Spaced-repetition flashcards
  • Import EPUB, PDF, TXT files
  • Offline reading support
  • Customizable reading themes and fonts
  • Pronunciation audio
Features
Read full description

Reading a book in another language? Stop breaking your flow to look words up. BookLight translates any word with a single tap โ€” and remembers it for you. BookLight is a EPUB & PDF & Txt reader built for language learners. Tap a word for an instant translation, and it's saved to your vocabulary automatically. Then spaced-repetition flashcards bring it back right before you'd forget โ€” so every reading session actually builds your vocabulary. No app-switching. No flashcards to make by hand. Perfect for language learners, foreign-book readers, and anyone studying for TOEFL or IELTS. Key Features: Start Reading in Seconds โ€” Free Classics Inside - Download from various free classics (Project Gutenberg) right inside the app โ€” no files to find, no setup. - Or import your own DRM-free EPUB & PDF & TXT files from your device. - Read offline anytime, with your reading progress saved and restored automatically. Tap to Translate โ€” Without Losing Context - Tap any word for an instant translation: meaning by part of speech, phonetics, and an example sentence. - Tap an inflected word and see its base form, too. - Hear the pronunciation read aloud with one tap. - Every word you tap is saved automatically โ€” together with the sentence and the book it came from. - Translate into 9 languages: Korean, Spanish, French, Japanese, Chinese, Russian, Hindi, Vietnamese, and Indonesian. Remember Every Word โ€” Spaced Repetition - Your vocabulary list builds itself as you read โ€” no manual entry. - Review with spaced-repetition (SRS) flashcards that resurface each word right before you forget it. - Tap any saved word to jump straight back to the exact spot in the book. - Keep a daily streak and a smart reminder nudges you only when words are actually waiting. Your Book Becomes an Audiobook โ€” AI Read-Aloud - A natural, human-like on-device AI voice reads your book aloud โ€” choose from 10 voices. - The sentence being read is highlighted, so you can follow along with your eyes and ears. - Playback keeps going with the screen off or while you use other apps. - Playback speed from 0.5x to 2x โ€” faster on the commute, slower before sleep. - Speech is synthesized on your device, so it works without an internet connection. Read Your Way, Day or Night - 7 fonts and 25 reading themes โ€” from Sepia and Night to Rose Quartz, Sage, and Midnight. - Adjust font size and line spacing until the page feels just right. - Choose how you read โ€” page turns or continuous scroll. - Read hands-free with auto-scroll โ€” 10 speed levels, and a single touch pauses instantly. - Full dark mode plus automatic system-theme sync. - Side-by-Side two-page display mode for comfortable reading on tablets. Loved by readers in 10+ countries. Supports 9 translation languages and works with any DRM-free EPUB or TXT file. Download BookLight today โ€” and turn every reading session into a vocabulary lesson! - Privacy Policy: https://pearlismylove.github.io/apps/book-light/privacy-policy.html - Terms And Conditions: https://pearlismylove.github.io/apps/book-light/terms-and-conditions.html - Support: https://pearlismylove.github.io/apps/book-light/support.html

About

ReadGem

Features
Read full description

Read books. Learn languages. Read the original. Compare translations. Understand more with AI. ReadGem turns reading into a natural way to learn languages. Explore the original text alongside its translation, compare how the same sentence is expressed across languages, and discover meaning through real books and real context. When a sentence is difficult, ask AI for an explanation. When a translation feels awkward, use AI to suggest a better one. Go beyond simply reading a translation โ€” read, compare, understand, and learn. Read the original and translation together Explore the original text alongside its translation and see how meaning moves from one language to another. Instead of studying isolated words and grammar, experience language through real sentences, expressions, and context from books. Reading becomes learning naturally. Compare translations across languages See how the same sentence is expressed in different languages. Compare translations sentence by sentence and discover differences in wording, expression, and nuance. Whether you're learning English or exploring another language, ReadGem helps you see beyond a single translation. Understand more with AI Some sentences need more than a translation. Ask AI to explain difficult sentences, expressions, context, and nuance. Explore why a sentence means what it does and gain a deeper understanding of both the original text and the language you're learning. Use AI not just to get an answer, but to understand what you're reading. Improve translations with AI Found a translation that sounds awkward or doesn't fully capture the original? Ask AI to suggest a better translation. Compare the suggestion with the original and decide whether it expresses the meaning more naturally and accurately. Exploring better translations can itself become part of learning a language. Read and listen Listen to sentences while you read. Hear pronunciation and rhythm while following the text, and use books to practice listening and pronunciation as well as reading. Everything you need for EPUB reading ReadGem also includes essential EPUB reading features: Table of contents and chapter navigation Highlights and bookmarks Automatic reading position saving Font and reading appearance settings Offline reading for downloaded books ReadGem is for you if you want to: Learn English by reading original books Learn languages naturally through reading Read original text alongside translations Compare expressions across different languages Understand difficult sentences with AI Explore better translations with AI Read. Compare. Understand. Improve. A book is more than something to read. It can also be a rich source of real language and context. With ReadGem, read the original, compare translations, understand with AI, and discover better ways to express every sentence.

Screenshots

BookLight4 screens
ReadGem2 screens

Verdict

The call

The clearest difference is in-app purchases: ReadGem at none against BookLight's 3. BookLight's advantage is iOS requirement (15.1 vs 17.6). 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. BookLight sells 3 in-app purchases, starting at $0.99 per month. ReadGem asks for nothing beyond the download.

UpkeepUpdate frequency

BookLight ships an update every 5 days, ReadGem every 4 days. The most recent releases landed on September 18, 2026 and September 24, 2026 respectively.

Scorecard2 real differences ยท 6 level
BookLight versus ReadGem: the parameters behind the verdict, then further details
ParameterBookLightReadGem
PriceFreeFree
Positive reviews100.0% of reviewsโ€”
Update frequencyEvery 5 daysEvery 4 days โ€” better
AdsNoNo
In-app purchasesYesNo โ€” better
MonetizationFree with in-app purchasesโ€”
DevicesiPhone, iPad, iPod โ€” betteriPhone, iPad
Requires iOS15.1 โ€” better17.6
Further details โ€” not scored
Size76 MB27 MB
Age rating4+4+
DeveloperJungjun LeeNEXTAOI, Inc

In-app purchases

3 purchases

BookLight

Subscriptions2
  • Monthly Plan$0.991 Month
  • Yearly Plan7 Days trial$7.991 Year
One-time1
  • Lifetime Plan$9.99
None

ReadGem

No in-app purchases

Questions

Is BookLight free?
BookLight is free to download, with in-app purchases available.
Is ReadGem free?
ReadGem is free to download, with no in-app purchases.
Do BookLight or ReadGem have ads?
Neither BookLight nor ReadGem shows ads.
Which is updated more often, BookLight or ReadGem?
BookLight ships an update every 5 days, and ReadGem every 4 days. Most recently, BookLight was updated on September 18, 2026 and ReadGem on September 24, 2026.

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