# n4Studies vs SELF U

n4Studies and SELF U both sit at 5.0 stars, but that hides the real split: 100% of n4Studies's written reviews are positive against 41% of SELF U's. n4Studies also leads on in-app purchases (none vs 7) and chart position (#186 vs unranked). SELF U's advantage is price (Free vs $1.99) and update cadence (every 5 weeks vs every 4 months). On rating, ratings volume and ads there is nothing between them.

SELF U is free to download; n4Studies costs $1.99 up front. SELF U sells 7 one-off in-app purchases. n4Studies asks for nothing beyond the download.

On the App Store both sit at effectively the same score — 5.0 for n4Studies against 5.0 for SELF U. Both are backed by a comparable volume of ratings — 1 and 1 respectively. Written reviews are what separate them: 100% of n4Studies's written reviews are positive against 41% of SELF U's.

n4Studies ships an update every 4 months, SELF U every 5 weeks. The most recent releases landed on August 7, 2026 and June 11, 2026 respectively.

## The numbers

| Metric | n4Studies | SELF U |
| --- | --- | --- |
| Price | $1.99 | **Free** |
| Rating | [5.0 (1 ratings)](https://appshunter.io/ios/app/n4studies/id680516901/reviews) | [5.0 (1 ratings)](https://appshunter.io/ios/app/self-u/id1217768492/reviews) |
| Number of ratings | 1 | 1 |
| Positive reviews | **100.0% of reviews** | 41.2% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 4 months | **Every 5 weeks** |
| Monetization | Paid | **Free with in-app purchases** |
| Best chart rank | **#186** | — |
| Size | 8 MB | 120 MB |
| Requires iOS | 16.0 | **12.0** |
| Devices | iPhone | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Chetta Ngamjarus](https://appshunter.io/developer/680516904) | [XeerSoft Thailand Co,Ltd.](https://appshunter.io/developer/548538383) |

## What reviewers say

### n4Studies

[App page](https://appshunter.io/ios/app/n4studies/id680516901)

**Currently charting:** #186 Top Paid · Education (US App Store)

This application simplifies sample size and study power calculations for various research designs. It offers tools for estimating population means and proportions, comparing groups, and analyzing different study types like case-control and randomized controlled trials. Results can be easily shared via email.

**Highlights:** Calculate sample size for infinite/finite populations, Compare two population means/proportions, Calculate sample size for various study designs, Calculate study power for comparisons, Calculate study power for various study designs, Share results via email

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases:** none


### SELF U

[App page](https://appshunter.io/ios/app/self-u/id1217768492)

This platform offers a comprehensive online learning experience with courses taught by experts across various subjects. Access lessons anytime, anywhere, and manage your learning journey conveniently. Enhance your skills and knowledge with a wide range of educational content.

**Highlights:** Anywhere, Anytime Learning, Class Booking Management, Full Coverage of Study Areas, Expert and Famous Instructors, Self-Development Courses

**Features:** macOS Compatibility

**In-app purchases (7)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Pack Read Around (Lesson 1-4) | $64.99 | one-time |
| Advanced Vocab + Reading | $119.99 | one-time |
| Advanced Vocab & Reading | $119.99 | one-time |
| Complete 5,000 Vocabularies | $139.99 | one-time |
| Ultimate Writing ปี 2559 | $174.99 | one-time |
| Advanced Writing (เทอม 1/61) | $209.99 | one-time |
| Advanced Admission (เทอม 1/60) | $299.99 | one-time |


## Frequently asked questions

### Is n4Studies free?

n4Studies costs $1.99, with no in-app purchases.

### Is SELF U free?

SELF U is free to download, with in-app purchases available.

### Which has better reviews, n4Studies or SELF U?

n4Studies and SELF U are both rated 5.0 out of 5 on the App Store, from 1 and 1 ratings respectively.

### Do n4Studies or SELF U have ads?

Neither n4Studies nor SELF U shows ads.

### Which is updated more often, n4Studies or SELF U?

n4Studies ships an update every 4 months, and SELF U every 5 weeks. Most recently, n4Studies was updated on August 7, 2026 and SELF U on June 11, 2026.

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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*