# E vs ROI大师

The clearest difference is in-app purchases: E at none against ROI大师's 7. ROI大师's advantage is iOS requirement (13.0 vs 15). On price, update cadence, ads and device support there is nothing between them.

Both are free to download. ROI大师 sells 7 in-app purchases, starting at $0.99 per month. E asks for nothing beyond the download.

Both ship on a similar rhythm, roughly every 2 weeks. The most recent releases landed on August 18, 2026 and August 13, 2026 respectively.

## The numbers

| Metric | E | ROI大师 |
| --- | --- | --- |
| Price | Free | Free |
| Positive reviews | — | 25.0% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 2 weeks | Every 2 weeks |
| Monetization | — | Freemium |
| Size | 40 MB | 63 MB |
| Requires iOS | 15 | **13.0** |
| Devices | iPhone, iPod | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [CARMAX CO., LTD.](https://appshunter.io/developer/1527718609) | [丹宁 冯](https://appshunter.io/developer/1452086482) |

## What reviewers say

### E

[App page](https://appshunter.io/ios/app/e-mirror-pro/id6739514204)

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

**In-app purchases:** none


### ROI大师

[App page](https://appshunter.io/ios/app/roi/id6743304426)

This tool helps e-commerce operators accurately calculate advertising return on investment (ROI) and optimize pricing strategies. It provides detailed data on ad spend, commissions, profit margins, and break-even points to drive data-informed decisions and reduce wasteful spending.

**Highlights:** Calculate advertising ROI, Optimize product pricing, Analyze ad spend and commissions, Estimate break-even ROI, Simulate costs (logistics, fees), Analyze ad monetization LTV

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

**In-app purchases (7)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 电商ROI计算器月度会员 | $0.99 | per month |
| 电商ROI计算器周度会员 | $0.99 | per 7 days |
| 电商ROI计算器年度会员 | $7.99 | per year |
| 电商ROI计算器周卡会员 | $0.99 | one-time |
| 电商ROI计算器月卡会员 | $2.99 | one-time |
| 电商ROI计算器年卡会员 | $12.99 | one-time |
| 电商ROI计算器终身会员 | $14.99 | one-time |


## Frequently asked questions

### Is E free?

E is free to download, with no in-app purchases.

### Is ROI大师 free?

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

### Do E or ROI大师 have ads?

Neither E nor ROI大师 shows ads.

### Which is updated more often, E or ROI大师?

E ships an update every 2 weeks, and ROI大师 every 2 weeks. Most recently, E was updated on August 18, 2026 and ROI大师 on August 13, 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.*