# AddCalculator vs Useful Lock Screen Memo

The clearest difference is in-app purchases: AddCalculator at none against Useful Lock Screen Memo's 1. AddCalculator also leads on iOS requirement (17.0 vs 26.0). On price, update cadence, ads and device support there is nothing between them.

Both are free to download. Useful Lock Screen Memo sells 1 one-off in-app purchase. AddCalculator asks for nothing beyond the download.

AddCalculator ships an update every 5 days, Useful Lock Screen Memo weekly. The most recent releases landed on October 4, 2026 and October 24, 2026 respectively.

## The numbers

| Metric | AddCalculator | Useful Lock Screen Memo |
| --- | --- | --- |
| Price | Free | Free |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | **No** | Yes |
| Ads | Yes | Yes |
| Update frequency | **Every 5 days** | Weekly |
| Monetization | Ad-supported | — |
| Size | 6 MB | 118 MB |
| Requires iOS | **17.0** | 26.0 |
| Devices | iPhone | **iPhone, iPad** |
| Age rating | 4+ | 4+ |
| Developer | [Minseong Kim](https://appshunter.io/developer/1707019155) | [katapu.net](https://appshunter.io/developer/381898924) |

## What reviewers say

### AddCalculator

[App page](https://appshunter.io/ios/app/addcalculator/id6466179281)

This utility automatically sums numbers as you input them, streamlining quick calculations. Create custom buttons for frequently used values and review your calculation history. It offers undo/redo functionality and supports two color themes for a personalized experience.

**Highlights:** Automatic addition on number press, Customizable number buttons, Calculation history log, Undo and redo functionality, Dual color mode support

**Features:** macOS Compatibility

**In-app purchases:** none


### Useful Lock Screen Memo

[App page](https://appshunter.io/ios/app/useful-lock-screen-memo/id6799839918)

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Remove Ads | $5.99 | one-time |


## Frequently asked questions

### Is AddCalculator free?

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

### Is Useful Lock Screen Memo free?

Useful Lock Screen Memo is free to download, with in-app purchases available.

### Do AddCalculator or Useful Lock Screen Memo have ads?

Both AddCalculator and Useful Lock Screen Memo show ads.

### Which is updated more often, AddCalculator or Useful Lock Screen Memo?

AddCalculator ships an update every 5 days, and Useful Lock Screen Memo weekly. Most recently, AddCalculator was updated on October 4, 2026 and Useful Lock Screen Memo on October 24, 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.*