504 Reviews: Is It Legit?

Customer Experience

Positive experience73.0% of reviews
Neutral4.8% of reviews
Negative experience22.2% of reviews

~ Based on 63 written reviews from the US App Store.

What users say about 504

Is 504 Safe?

504 - Vocabulary Builder appears safe based on user ratings. AppsHunter Safety Score for 504 is 95/100.

This assessment is based on 4,600 user ratings, with an App Store average of 4.8/5.

Safety Analysis

94.6% of ratings point to a safe experience
2.7% of ratings suggest some concerns
2.7% of ratings point to a risky experience

~ Based on 4,599 App Store ratings for 504.

Is 504 Legit?

504 - Vocabulary Builder appears to be a legitimate app. AppsHunter Legitimacy Score for 504 is 100/100.

Based on 100 of 100 points across 7 verification signals from App Store and developer data.

Top reviews

English Audio Reading French Words Not Good

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.
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Response from developer

Hi — thank you for this honest feedback, and I’m really sorry the audio made the cards unusable for you. That must’ve been frustrating after you’d already set everything up. Often this happens because the app falls back to the device’s default text‑to‑speech voice (which can be an English voice) instead of a French voice. A couple of things that usually help: - In the app: Settings → Audio/Pronunciation (if present) → pick “French” or a French voice. - If you don’t see that, check your device TTS settings (iOS: Settings → Accessibility → Spoken Content → Voices; Android: Settings → System → Languages & input → Text‑to‑speech) and select a French voice there. If you’d like, tell me your device and OS (iPhone/Android + version) and I’ll give exact steps. If the problem persists despite those changes, please contact Help → Contact Us in the app or reply here with the app version and a screenshot of the card — we’ll investigate and prioritize a fix (and look into adding native French audio for those vocab sets). Thanks again for flagging this — we really appreciate it and want to make the app reliable for learners like you.

Excellent Vocabulary Learning App!

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!

doesn't work

I can't open the app. what's the problem?

Response from developer

Hello, please update the app.

Questions

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
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Response from developer

Hello, thanks for your comment. We will make some adjustments accordingly.

Terrible

Please I’m waiting for new update .
This app doesn’t even open properly!

Отличное приложение для запоминания слов

Очень полезное приложение! Слова сопровождаются 📚 картинками, что помогает запомнить лучше. Рекомендую!

Response from developer

Нам очень приятно, спасибо!

504 review

It’s the best app that I have used in my entire life, I really appreciate creating such an amazing app

Response from developer

We are glad you like our app 😍

Fix problem

Hello,it is great app.However,I updated the software but it doesn't work anymore

Data tracking

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
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Response from developer

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.

Data tracking

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.
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Response from developer

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.

Data tracking

Sketchy they want to track you across the different services you use. Instant delete.

Response from developer

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.

Any other app?

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

Fantastic App for Learning English Vocabulary!

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.
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Awesome app

This is app good and easy for learning

Suggestion

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

Response from developer

We took it as a valuable feedback, thanks!

Review

Great. Thanks.

My idea 💡

Easy to learn 😉

Improvement!

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.

Response from developer

We are so happy to hear that 🤩

A

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

Response from developer

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!

Don’t have dark mode

😵‍💫😵‍💫😵‍💫😵‍💫