# PerfectPrep vs Ace AP STEM

The clearest difference is in-app purchases: Ace AP STEM at none against PerfectPrep's 11. Ace AP STEM also leads on review sentiment (100% vs 67%) and rating (5.0 vs 4.6). PerfectPrep's advantage is update cadence (fortnightly vs every 3 months) and ratings volume (878 vs 3). On price, ads and device support there is nothing between them.

Both are free to download. PerfectPrep sells 9 in-app purchases, starting at $4.99 per 7 days. Ace AP STEM asks for nothing beyond the download.

Ace AP STEM holds the better App Store score, 5.0 against 4.6. That said, the two scores are not equally well evidenced: PerfectPrep has 878 ratings behind it against 3, so its average is the more settled of the two. Written reviews point the same way: 67% of PerfectPrep's written reviews are positive against 100% of Ace AP STEM's.

PerfectPrep ships an update fortnightly, Ace AP STEM every 3 months. The most recent releases landed on October 24, 2026 and October 20, 2026 respectively.

## The numbers

| Metric | PerfectPrep | Ace AP STEM |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [4.6 (878 ratings)](https://appshunter.io/ios/app/perfectprep-act-and-sat-prep/id1524653663/reviews) | **[5.0 (3 ratings)](https://appshunter.io/ios/app/ace-ap-stem/id6780169317/reviews)** |
| Number of ratings | **878** | 3 |
| Positive reviews | 66.7% of reviews | **100.0% of reviews** |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | **Fortnightly** | Every 3 months |
| Monetization | Free with in-app purchases | **Free** |
| Size | 122 MB | 24 MB |
| Requires iOS | **13.0** | 15.6 |
| Devices | iPhone, iPod | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Mosaic S.r.l.](https://appshunter.io/developer/570748343) | [Linh Do](https://appshunter.io/developer/6780169319) |

## What reviewers say

### PerfectPrep

[App page](https://appshunter.io/ios/app/perfectprep-act-and-sat-prep/id1524653663)

Prepare for standardized college entrance exams with a personalized study plan, practice tests, and detailed explanations. Track your progress, review concepts with flashcards, and access video lessons to boost your score. Get expert tips and predictions to ace your ACT or SAT.

**Highlights:** Personalized study plans, Subject-specific practice tests, Full practice exams, Detailed answer explanations, Flashcards for concept review, Video lessons and tutorials, Progress tracking and score prediction

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

**In-app purchases (9)**

| Purchase | Price | Billing |
| --- | --- | --- |
| PerfectPrep Premium 1 Week | $4.99 | per 7 days |
| PerfectPrep Premium 1 Week | $4.99 | per 7 days |
| PerfectPrep Premium 1 Month | $9.99 | per month |
| PerfectPrep Premium 1 Month | $9.99 | per month |
| PerfectPrep Premium 1 Month | $9.99 | per month |
| PerfectPrep Premium 1 Month | $14.99 | per month |
| PerfectPrep Premium 6 Months | $19.99 | per 6 months |
| PerfectPrep Premium 6 months | $39.99 | per 6 months |
| PerfectPrep Premium 6 Months | $39.99 | per 6 months |

**What reviewers like**

- 👍 Good app for SAT prep
- 👍 Easy to use with many useful features
- 👍 Helpful for studying and preparing for the SAT
- 👍 Great for students and anyone taking the SAT
- 👍 Awesome app

**What reviewers complain about**

- 🐛 Incorrect content and errors in practice questions
- 🐛 Software bugs and issues with practice tests
- 💰 Not completely free, some features require payment
- 🐛 Answers marked wrong even though they are correct

**Reported bugs**

- Constant notifications despite disabling them
- Time limits not accurate for practice tests
- Many typos in the app

**Requested features**

- Dark mode option
- More free practice content


### Ace AP STEM

[App page](https://appshunter.io/ios/app/ace-ap-stem/id6780169317)

This study toolkit helps AP STEM students deeply understand concepts and solve problems. It offers step-by-step solutions, gradual hints, and concept notes. Organize your learning with a personal study library and practice with related problems.

**Highlights:** Step-by-step problem solving, Gradual hints for self-solving, Generate concept notes, Personalized study library, Practice with related problems, Customizable study buddy

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

**In-app purchases:** none


## Frequently asked questions

### Is PerfectPrep free?

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

### Is Ace AP STEM free?

Ace AP STEM is free to download, with no in-app purchases.

### Which has better reviews, PerfectPrep or Ace AP STEM?

Ace AP STEM is rated higher. PerfectPrep averages 4.6 out of 5 from 878 ratings, while Ace AP STEM averages 5.0 from 3 ratings.

### Do PerfectPrep or Ace AP STEM have ads?

Neither PerfectPrep nor Ace AP STEM shows ads.

### Which is updated more often, PerfectPrep or Ace AP STEM?

PerfectPrep ships an update fortnightly, and Ace AP STEM every 3 months. Most recently, PerfectPrep was updated on October 24, 2026 and Ace AP STEM on October 20, 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.*