# i vs E

The clearest difference is price: i at Free against E's $9.99. i also leads on update cadence (every 6 days vs every 3 months) and review sentiment (43% vs 33%). E's advantage is in-app purchases (none vs 10) and ads (none vs shown). On device support there is nothing between them.

i is free to download; E costs $9.99 up front. i sells 10 one-off in-app purchases. E asks for nothing beyond the download.

i ships an update every 6 days, E every 3 months. The most recent releases landed on October 15, 2026 and June 4, 2026 respectively.

## The numbers

| Metric | i | E |
| --- | --- | --- |
| Price | **Free** | $9.99 |
| Rating | **[4.2 (10 ratings)](https://appshunter.io/ios/app/i-memorize-sheet/id803026043/reviews)** | — |
| Number of ratings | **10** | — |
| Positive reviews | **42.9% of reviews** | 33.3% of reviews |
| In-app purchases | Yes | **No** |
| Ads | Yes | **No** |
| Update frequency | **Every 6 days** | Every 3 months |
| Monetization | **Free with in-app purchases** | Paid |
| Size | 67 MB | 174 MB |
| Requires iOS | 18.0 | **12.0** |
| Devices | **iPhone, iPad** | iPad |
| Age rating | 4+ | 4+ |
| Developer | [BrainApp LLC](https://appshunter.io/developer/726018559) | [Suzuki Educational Software Co.,Ltd.](https://appshunter.io/developer/585512975) |

## What reviewers say

### i

[App page](https://appshunter.io/ios/app/i-memorize-sheet/id803026043)

This app allows users to hide text in study materials using a filter, mimicking a red sheet for effective memorization. It supports photos and PDFs, enabling studying anytime, anywhere with just a smartphone.

**Highlights:** Hide text with red filter effect, Study photos and PDFs, Add check marks for progress, Efficient study with navigation, Use anytime, anywhere

**In-app purchases (10)**

| Purchase | Price | Billing |
| --- | --- | --- |
| i-Memorize Sheet Remove ADs Option | $0.99 | one-time |
| imc00010 | $0.99 | one-time |
| imc00020 | $0.99 | one-time |
| i-Mem-Contents imc00030 | $0.99 | one-time |
| i-Mem-Contents imc00040 | $0.99 | one-time |
| i-Mem-Contents imc00010 | $0.99 | one-time |
| i-memorize Sheet File-Limit release add-on | $2.99 | one-time |
| i-memorize Sheet PDF page-Limit release add-on | $4.99 | one-time |
| Pro licence(campaign) | $5.99 | one-time |
| i-memorize Sheet Limit release add-on | $6.99 | one-time |


### E

[App page](https://appshunter.io/ios/app/e-volvox/id1117257383)

Organize and visualize information by joining round plates into rings. Add text, photos, videos, and illustrations to plates, then structure them into themes. Plates can be displayed in 3D and enlarged for presentations.

**Highlights:** Add media to round plates, Join plates into rings for themes, Structure plates by associating with other rings/plates, 3D plate display, Enlarge plates and flick through content, Presentation mode, Share via AirDrop, Import/export data via iTunes

**In-app purchases:** none


## Frequently asked questions

### Is i free?

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

### Is E free?

E costs $9.99, with no in-app purchases.

### Do i or E have ads?

i shows ads; E does not.

### Which is updated more often, i or E?

i ships an update every 6 days, and E every 3 months. Most recently, i was updated on October 15, 2026 and E on June 4, 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.*