Comparison

Stacks vs Flagsay

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

Head to head
About

Stacks

Create flashcards from your own experiences and conversations. This app uses spaced repetition to help you remember vocabulary longer with less study. It supports over 100 languages and offers offline study capabilities.

Highlights
  • Create cards from stories and conversations
  • Spaced repetition system (FSRS)
  • Offline study mode
  • Automatic translations
  • Supports over 100 languages
  • Romanization for select scripts
  • Clean, minimal interface
Features
Read full description

Your stories are better. Life's too short to cram from borrowed lists. Stacks turns trips and conversations into cards, then spaced-repetition (FSRS) handles the science. Episodic memory meets spaced repetition. Dream team. Benefits: โ€ข Keep momentum anywhere โ€“ Study offline on flights, trains, or dead zones. โ€ข Stay in sync across devices โ€“ Your progress follows you automatically. โ€ข Focus without distractions โ€“ No ads, just learning. โ€ข Create cards in seconds โ€“ Automatic translations speed up card creation. โ€ข Learn with clearer meanings โ€“ Premium DeepL translations offer high accuracy and context. โ€ข Remember longer with less study โ€“ FSRS schedules reviews at the right time. โ€ข Learn the language you care about โ€“ Supports over 100 languages. โ€ข Crack non-Latin scripts faster โ€“ Romanization for select languages like Japanese, Arabic, Russian, and Hindi. โ€ข Feel calm while you study โ€“ A clean, minimal interface that gets out of the way. Free and Plus Create up to 40 cards for free. Upgrade to Stacks Plus for unlimited cards, DeepL translations, spaced repetition customisation, and more. Perfect for language learners, students, and polyglots who want to study offline, master vocabulary, and remember more with flashcards. Privacy Policy: https://www.thestacksapp.com/privacy Terms of Service: https://www.thestacksapp.com/terms-of-service EUSA: https://www.apple.com/legal/internet-services/itunes/dev/minterms/

About

Flagsay

Features
Read full description

Flagsay is an AI-powered language learning app built around real-world object scanning, spirit companion chat, and story-based practice. Core features: 1. Object Scan Learning: Use camera or photo library to identify objects and get vocabulary, pronunciation, examples, and translations. 2. Spirit Companion Chat: Turn scanned objects into AI companions and practice conversations with different personas. 3. Story Generation Practice: Generate learning stories from your daily vocabulary or custom words for reading and speaking practice. 4. Vocabulary and Progress: Save words, sync core learning data, and track your daily usage and learning progress. For any questions or suggestions, please contact us at support@flagsay.com Privacy Policy: https://flagsay.app/privacy Terms of Use: https://flagsay.app/terms

Screenshots

Stacks4 screens
Flagsay3 screens

Verdict

The call

Stacks and Flagsay are too close to call on the numbers: across 6 compared parameters โ€” price, update cadence, ads and in-app purchases among them โ€” neither pulls far enough ahead to decide it. What separates them is feature set and interface, not measurable difference.

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. Stacks sells 2 in-app purchases, starting at $9.99 per 3 months and Flagsay sells 2 in-app purchases, starting at $2.99 per month. Whichever you choose, the download price is not the number that matters.

UpkeepUpdate frequency

Both ship on a similar rhythm, roughly every 3 months. The most recent releases landed on October 16, 2026 and October 5, 2026 respectively.

ScorecardNo meaningful differences
Stacks versus Flagsay: the parameters behind the verdict, then further details
ParameterStacksFlagsay
PriceFreeFree
Positive reviews100.0% of reviewsโ€”
Update frequencyEvery 3 monthsEvery 3 months
AdsNoNo
In-app purchasesYesYes
MonetizationFreemiumโ€”
DevicesiPhone, iPadiPhone, iPad
Requires iOS16.4 โ€” better17.0
Further details โ€” not scored
Size77 MB18 MB
Age rating4+4+
DeveloperLewis HoyShanghai Sunrise Chime Technology Co., Ltd.

In-app purchases

2 purchases

Stacks

Subscriptions2
  • Stacks+ Quarterly$9.993 Months
  • Stacks+ Yearly$27.991 Year
2 purchases

Flagsay

Subscriptions2
  • CaiQi Talk Pro Monthly Subscription$2.991 Month
  • CaiQi Talk Pro Yearly Subscription$29.991 Year

Questions

Is Stacks free?
Stacks is free to download, with in-app purchases available.
Is Flagsay free?
Flagsay is free to download, with in-app purchases available.
Do Stacks or Flagsay have ads?
Neither Stacks nor Flagsay shows ads.
Which is updated more often, Stacks or Flagsay?
Stacks ships an update every 3 months, and Flagsay every 3 months. Most recently, Stacks was updated on October 16, 2026 and Flagsay on October 5, 2026.

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