# 504 - Vocabulary Builder — user reviews > 62 indexed App Store user reviews of 504 by Nefarius Apps, rated 4.80/5 from 4,603 ratings. - Source: https://appshunter.io/ios/app/504-vocabulary-builder/id1452101398/reviews - App overview in markdown: https://appshunter.io/ios/app/504-vocabulary-builder/id1452101398.md - Rating breakdown: 5★ 4,014 · 4★ 340 · 3★ 125 · 2★ 41 · 1★ 83 ## What do users think of 504? Overall sentiment: neutral **Pros** - 🚀 Easy to learn - 👍 Useful vocabulary practice - 🚀 Convenient for learning on the go **Cons** - 🐛 Bugs and glitches in latest version - 🔒 Concerns about data tracking - 🔊 Issues with pronunciation and audio **Commonly reported bugs** - Pronunciation not working in latest version - Lessons for second half of book blocked behind paywall - Compatibility issues with older devices **Most requested features** - Add part of speech for each word - Include a note box for personal examples - Add dark mode option ## Newest reviews (11 of 62) ### 3/5 — doesn't work *2025-02-14, version 8.0.0* I can't open the app. what's the problem? ### 4/5 — Suggestion *2023-11-01, version 6.2.0* Tnx for you app but i wanna say the reader wasnt good . She reads rapidly n i couldnt realize very well as a amateur person. at least for simple parts should read slowly . Tnx again ### 5/5 — A *2023-06-13* Don’t update the app if you already installed the old version, because in the updated version you need to pay money if you want access to lessons of secend half of the book its kind of cheat and I feel stupid that I updated the app **Developer response:** Hello, the subscription package system has already been in the app from the first version. We need capital to keep development ongoing as every development team. Regardless, we thanks for the honest feedback! ### 5/5 — Don’t have dark mode *2023-02-11, version 5.9.0* 😵‍💫😵‍💫😵‍💫😵‍💫 ### 4/5 — Is it 504 essential word book?? *2022-08-31, version 5.3.0* Is it 504 essential word book?? ### 5/5 — Excellent *2022-05-28, version 4.8.0* Very good ### 3/5 — Dont update *2022-03-24, version 4.8.0* Don’t update the app if you already installed the old version, because in the updated version you need to pay money if you wand to access to lessons of the second half of the book. It’s kind of cheat and I feel stupid that i updated the app. ### 5/5 — Review *2022-01-12, version 4.4.1* this app perfect for who want to learn English ### 4/5 — Useful vocabulary exercising on the go *2022-01-11, version 4.4.1* It’s very convenient to use this app instead of the book for learning and reviewing vocabulary any time and in any situation. Yet some other features can be added to make it better, like 1-adding part of speech of each word.2- adding a note box in each word’s place to add notes and personal examples. Thanks for your attention. ### 5/5 — Faydalı ve sade *2021-12-08, version 4.2.0* Hedefe yönelik olması güzel olmuş ✍🏼 ### 5/5 — Needs some additions *2021-12-08, version 4.2.0* What about adding notification feature? For example, we select the words that we are not familiar. For specific intervals, we receive notifications of these words with their vocabularies. It is splendid. However adding British accent and phonetic spelling would be awesome. ## Most critical reviews (10 lowest-rated) ### 1/5 — English Audio Reading French Words Not Good *2025-12-26, version 8.5.0* I set up the app to ostensibly teach me intermediate-level French vocabulary. The French words appeared in individual cards with French synonyms and example sentences. All fine so far. But when I pressed the audio pronunciation button next to the French vocab words, the built-in text-to-speech reader was an English voice which wrecked the pronunciation of the French words. This made the app essentially useless for my purposes. Unfortunate to say the least. ### 1/5 — Terrible *2024-08-10, version 7.4.0* Please I’m waiting for new update . This app doesn’t even open properly! ### 1/5 — Data tracking *2024-05-22, version 7.1.0* Sketchy they want to track you across the different apps and websites you use: your user id, device id, usage data, and diagnostics. Instant delete. Edit: don’t believe their response, they would not be required to ask for consent if they didn’t track your data across services owned by other companies. Edit again: the person responding to reviews clearly doesn’t understand data tracking across apps and websites from other companies, sketchy when your app is doing it and it’s literally disclosed on your product page ha ### 1/5 — Data tracking *2024-05-20* Sketchy they want to track you across the different apps and websites you use: your user id, device id, usage data, and diagnostics. Instant delete. Edit: don’t believe their response, they would not be required to ask for consent if they didn’t track your data across services owned by other companies. **Developer response:** Hello, thanks for the review. Allowing tracking doesn't mean the app can access all the data on your phone you have. It means the app can identify you ONLY in 504 app during the usage of the app. It helps us to show you the best content. Edit: Hello again. No mobile application can see the data of another mobile application. This is not possible with Apple products. This applies both to us and to other mobile apps. ### 1/5 — Data tracking *2024-05-17* Sketchy they want to track you across the different services you use. Instant delete. **Developer response:** Hello, thanks for the review. Allowing tracking doesn't mean the app can access all the data on your phone you have. It means the app can identify you ONLY in 504 app during the usage of the app. It helps us to show you the best content. ### 1/5 — The worst App I’ve ever seen! *2022-12-22, version 5.9.0* This was the worst app I’ve ever seen! You just can use the flashcards. Nothing else! The pronunciation sounds robot-like. It’s not the original one of the book. And it’s constantly asking you to go on premium. I just uninstalled it after day one. ### 1/5 — Lier *2022-10-28, version 5.7.0* You are lier. First give an update as bug fixes. But after update half of book block and i can not see them. Do you know why? Because I am not a premium user!! What a surprise. You are lier ### 1/5 — Not free *2022-03-14, version 4.8.0* It’s not free to use after lesson 20😑 ### 1/5 — Ads.. *2021-12-08, version 4.2.0* Annoying ads.. ### 1/5 — My app doesn’t have any sound *2021-11-24, version 4.0.0* I have a problem with pronunciation I can’t hear ## Most praised reviews (10 highest-rated) ### 5/5 — Excellent Vocabulary Learning App! *2025-08-14, version 8.0.0* This is one of the most useful apps I’ve used to improve my English vocabulary. The word of the day feature makes learning both fun and consistent, helping me practice regularly. The interface is clean, easy to use, and the content is high-quality. Highly recommended! ### 5/5 — Questions *2024-12-17, version 7.7.0* I downloaded this app like 2 minutes ago tbh but i have some questions: 1: is there like a premium that you have to pay for? Because I read all the reviews (i like reading reviews for some reason) and some of them complained about premium and I downloaded it expecting to see premium or something but it just said you are already premium so I'm confused on that, 2: the words/lessons, how is words like legend, amend, resign, etc in the last/hardest(????) lesson and words like qualify, abandon, oath, etc in the first/easiest(????) so I'm really confused ### 5/5 — 504 review *2024-06-04, version 7.1.0* It’s the best app that I have used in my entire life, I really appreciate creating such an amazing app ### 5/5 — Fix problem *2024-05-23, version 7.1.0* Hello,it is great app.However,I updated the software but it doesn't work anymore ### 5/5 — Any other app? *2024-04-25, version 7.0.1* This app is fantastic, you have to pay money for more updates, but its little money , is there any other app like this by you ??? Harikasınız , çok güzel uygulama , oyunla öğretiyor kelemeleri , keşke başka uygulamalar da yapsanız haberimiz olsa ingilizce için ### 5/5 — Fantastic App for Learning English Vocabulary! *2024-04-23, version 7.0.0* I've been using this app for a few weeks now, and I must say, it's truly fantastic! As someone who is trying to improve their English vocabulary, I find this app incredibly helpful. The variety of words it offers, along with their definitions, example sentences, and even pronunciation guides, make it easy to understand and remember new words. The quizzes and exercises are fun and engaging, and they really help reinforce what I've learned. Plus, I love how the app tracks my progress, showing me how many words I've mastered and how much I've improved over time. It's like having a personal English tutor in my pocket! Highly recommend this app to anyone looking to expand their English vocabulary in a fun and effective way. ### 5/5 — Awesome app *2023-11-11, version 6.2.0* This is app good and easy for learning ### 5/5 — Review *2023-09-30, version 6.2.0* Great. Thanks. ### 5/5 — My idea 💡 *2023-08-24, version 6.2.0* Easy to learn 😉 ### 5/5 — Improvement! *2023-08-23, version 6.2.0* Very excellent practice! Im not a english person so this helps me a lot by learning all these words and the sentences that included words that are previous lesson practice. --- *Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-09-04.*