Comparison

American Heritage® Dictionary vs Thai Fast Dictionary

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

Head to head
About

American Heritage® Dictionary

Access a comprehensive digital dictionary with nearly 300,000 terms and thousands of sound files. Features include advanced search, etymology, and AI-powered tools for deeper understanding and language learning.

Highlights
  • Full dictionary text
  • 33,000+ example sentences
  • 64,000+ recorded sound files
  • Three-way cross-referencing search
  • Etymology with root links
  • AI Teacher for ESL students
  • Offline use
Features
Read full description

*NOTE: there is a newer version of American Heritage® Dictionary available on the AppStore. Tap on the "Enfour, Inc." link for AHD5. The entire 2,074 page, 7.5 pound dictionary with its nearly 300,000 terms –plus 64 thousand recorded sound files by native speakers -all available instantly at your fingertips. ________________________________________ "In the battle of the Big Three dictionaries, American Heritage® stands out on iPhone" (4 mice) — MacWorld ________________________________________ More than 33,000 written examples, totaling 4,222,000 words, makes this largest mobile dictionary on ANY platform The indexes alone are larger than most brand-name dictionaries. Even without the sound files, AHD would still be the largest dictionary in the AppStore. Main Features: ● the entire text of this best selling book ● complete front matter and appendices ● three-way cross-referencing search ● real-time progressive look-up ● wildcard pattern searches (with * ?) ● spelling suggestion dictionary included ● internal hyperlinking & supports copy/paste ● pop-up pronunciation symbols chart ● IPA pronunciation symbol conversion ● etymology (word history) with root links ● professionally recorded sound files ● zoomable graphics ● fallback online search for esoteric or archaic words and the latest slang ● unique two-way external application interaction — first iPhone dictionary with external linking and now most advanced! ● bookmarks with editable notations ● automatic search history ● an "AI Teacher" for deeper explanations or help for ESL students in 98 languages ● AI boosted anagram generator ● "Today" & LockScreen widgets ● 3D Touch support ● DarkMode support ● Siri support ● iPad multi-screen and Drag & Drop ● iPhone 17 & iOS26 support ● iPhone, iPod, iPad and macOS support ● complete offline use - no Internet connection The renowned American Heritage® Usage Panel, a group of more than 200 distinguished writers, scholars, and scientists, offers advice on problems of grammar and style; engaging notes explain word histories and clarify differences among synonyms; thousands of quotations and example sentences show words in context; and elegant definitions are enhanced by numerous full-color photographs, drawings, and maps, making this one of the most complete reference tool available on any mobile platform. Reviews for the application: "As apps go, only Enfour’s American Heritage® Dictionary stands out for its graphic appeal and functionality. Although I was pleased to have so much lexical firepower in such a compact form, I was annoyed at how poorly the other dictionaries present on the platform." (4 mice) — MacWorld Editor's Choice. ranking = "Great" — MacLife Reviews of the print version: "The Best Dictionary...Designed to appeal to the eye as well as the mind, it is notable for its imaginative illustrations....This is a great family dictionary, and ideal for schoolrooms." — The Courier Journal "This dictionary, now in its fourth edition, makes it fun to look up definitions of words....This up-to-date and eminently useful dictionary features a fabulous full-color design that quickly and effectively guides users to the information they seek." — Library Journal ________________________________________ The American Heritage® Dictionary of the English Language, Fourth Edition published by Houghton Mifflin Harcourt Publishing Company. All rights reserved. http://www.hmco.com ________________________________________ Powered by Enfour's "UniDict® Engine 16" —thesaurus links work with these products: "Roget's II: New Thesaurus" "Companion Thesaurus" "Companion Synonyms" and many more

About

Thai Fast Dictionary

Access an extensive offline dictionary with definitions and examples across multiple languages. An integrated AI chatbot offers instant assistance for clarifying terms, expanding vocabulary, and practicing pronunciation.

Highlights
  • Offline global standard database
  • Extensive word repository
  • Definitions and examples
  • Integrated AI chatbot
  • Instant assistance
  • Pronunciation practice
Features
Read full description

Thai Fast Dictionary is a Thai↔English dictionary built for speed. The entire dictionary lives on your device, so lookups are instant — no internet connection required. FEATURES • Instant Thai↔English word lookup, no waiting on a server • Clear definitions with parts of speech, example sentences, and synonyms • Search history and a favorites list, so you can find words you've looked up before • Two vocabulary games — Quiz and Hang Pig — to help you learn as you go • Works fully offline once installed Whether you're a Thai speaker learning English or an English speaker learning Thai, Thai Fast Dictionary keeps a complete dictionary in your pocket. Thai Fast Dictionary is free to use, supported by ads. An optional Advance Access subscription removes ads and unlocks unlimited daily lookups. Subscription terms: • Advance Access is available as a monthly or yearly auto-renewing subscription, billed to your Apple ID • Subscriptions renew automatically unless auto-renew is turned off at least 24 hours before the end of the current period • Manage or cancel anytime in your Apple ID account settings • Payment is charged to your Apple ID account upon confirmation of purchase Privacy Policy: https://thaifastdict.com/privacy_policy.html Terms of Use: https://thaifastdict.com/term_of_use.html

Screenshots

American Heritage® Dictionary4 screens
Thai Fast Dictionary4 screens

Verdict

The call

The clearest difference is price: Thai Fast Dictionary at Free against American Heritage® Dictionary's $12.99. Thai Fast Dictionary also leads on rating (5.0 vs 4.7). American Heritage® Dictionary's advantage is ads (none vs shown) and ratings volume (199 vs 1). On review sentiment, update cadence, in-app purchases and monetization model 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

Thai Fast Dictionary is free to download; American Heritage® Dictionary costs $12.99 up front. American Heritage® Dictionary sells 1 one-off in-app purchase and Thai Fast Dictionary sells 7 in-app purchases, starting at $0.99 per month. Whichever you choose, the download price is not the number that matters.

ReceptionRating · Positive reviews · Number of ratings

Thai Fast Dictionary holds the better App Store score, 5.0 against 4.7. That said, the two scores are not equally well evidenced: American Heritage® Dictionary has 199 ratings behind it against 1, so its average is the more settled of the two. Written reviews complicate that: 66% of American Heritage® Dictionary's written reviews are positive against 60% of Thai Fast Dictionary's, so the app with the better star average is not the one people write more warmly about.

UpkeepUpdate frequency

American Heritage® Dictionary ships an update every 2 months, Thai Fast Dictionary every 6 weeks. The most recent releases landed on September 23, 2026 and September 24, 2026 respectively.

Scorecard5 real differences · 5 level
American Heritage® Dictionary versus Thai Fast Dictionary: the parameters behind the verdict, then further details
ParameterAmerican Heritage® DictionaryThai Fast Dictionary
Price$12.99Free — better
Rating4.7 (199 ratings)5.0 (1 ratings) — better
Positive reviews65.6% of reviews — better59.6% of reviews
Number of ratings199 — better1
Update frequencyEvery 2 monthsEvery 6 weeks — better
AdsNo — betterYes
In-app purchasesYesYes
MonetizationFree with in-app purchasesFree with in-app purchases
DevicesiPhone, iPad, iPod, Mac — betteriPhone, iPad, iPod
Requires iOS12.0 — better14.0.0
Further details — not scored
Size385 MB143 MB
Age rating9+4+
DeveloperEnfour, Inc.THAI FAST COMPANY LIMITED

Customer experience

American Heritage® Dictionary

All ratings199 ratings
Positive94.5%
Neutral1.0%
Negative4.5%
Written reviews157 reviews
Positive65.6%
Neutral7.0%
Negative27.4%

Thai Fast Dictionary

All ratings1 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews94 reviews
Positive59.6%
Neutral3.2%
Negative37.2%

Bugs and requests

American Heritage® Dictionary

Reported bugs

3 issues
  • Compatibility issues with newer iOS versions
  • Unreliable audio playback
  • Unexpected behavior when clearing search history

Requested features

5 requests
  • Ability to bookmark words and organize them into custom categories
  • Improved search functionality (e.g. tapping words in definitions to jump to them)
  • Landscape mode support
  • Better sync/backup options for user data
  • More visual aids and illustrations

Thai Fast Dictionary

Not enough reviews yet to summarise bugs or requests.

In-app purchases

1 purchases

American Heritage® Dictionary

One-time1
  • Roget's II Thesaurus$4.99
7 purchases

Thai Fast Dictionary

Subscriptions4
  • Advance features$0.991 Month
  • Offline IPA with no Ads$2.991 Year
  • English meaning and samples$2.991 Year
Show 1 more
  • Advance features$4.991 Year
One-time3
  • Point 1000 pts$2.99
  • Point 5500 pts$12.99
  • Point 12000 pts$29.99

Questions

Is American Heritage® Dictionary free?
American Heritage® Dictionary costs $12.99, and also offers in-app purchases.
Is Thai Fast Dictionary free?
Thai Fast Dictionary is free to download, with in-app purchases available.
Which has better reviews, American Heritage® Dictionary or Thai Fast Dictionary?
Thai Fast Dictionary is rated higher. American Heritage® Dictionary averages 4.7 out of 5 from 199 ratings, while Thai Fast Dictionary averages 5.0 from 1 ratings.
Do American Heritage® Dictionary or Thai Fast Dictionary have ads?
Thai Fast Dictionary shows ads; American Heritage® Dictionary does not.
Which is updated more often, American Heritage® Dictionary or Thai Fast Dictionary?
American Heritage® Dictionary ships an update every 2 months, and Thai Fast Dictionary every 6 weeks. Most recently, American Heritage® Dictionary was updated on September 23, 2026 and Thai Fast Dictionary on September 24, 2026.

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