# Solution Dilution Calculator vs Locker

Solution Dilution Calculator and Locker both sit at 5.0 stars, but that hides the real split: 100% of Locker's written reviews are positive against 0% of Solution Dilution Calculator's. Locker also leads on price (Free vs $2.99) and update cadence (every 3 weeks vs every 22 months). Solution Dilution Calculator's advantage is in-app purchases (none vs 3) and iOS requirement (13 vs 15.6). On rating, ratings volume, ads and device support there is nothing between them.

Locker is free to download; Solution Dilution Calculator costs $2.99 up front. Locker sells 3 in-app purchases, starting at $1.49 per month. Solution Dilution Calculator asks for nothing beyond the download.

On the App Store both sit at effectively the same score — 5.0 for Solution Dilution Calculator against 5.0 for Locker. Both are backed by a comparable volume of ratings — 1 and 2 respectively. Written reviews are what separate them: 0% of Solution Dilution Calculator's written reviews are positive against 100% of Locker's.

Solution Dilution Calculator ships an update every 22 months, Locker every 3 weeks. The most recent releases landed on September 10, 2026 and September 5, 2026 respectively.

## The numbers

| Metric | Solution Dilution Calculator | Locker |
| --- | --- | --- |
| Price | $2.99 | **Free** |
| Rating | [5.0 (1 ratings)](https://appshunter.io/ios/app/solution-dilution-calculator/id1353265965/reviews) | [5.0 (2 ratings)](https://appshunter.io/ios/app/locker-password-manager/id1634798510/reviews) |
| Number of ratings | 1 | **2** |
| Positive reviews | 0.0% of reviews | **100.0% of reviews** |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 22 months | **Every 3 weeks** |
| Monetization | Paid | **Free with in-app purchases** |
| Size | 1 MB | 10 MB |
| Requires iOS | **13** | 15.6 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Nitrio](https://appshunter.io/developer/321121189) | [晖 姚](https://appshunter.io/developer/878190315) |

## What reviewers say

### Solution Dilution Calculator

[App page](https://appshunter.io/ios/app/solution-dilution-calculator/id1353265965)

This utility app helps users calculate the precise volume of stock concentrate needed to create a diluted solution of a specific concentration and volume. It supports various concentration units and is designed for educational and research laboratory use.

**Highlights:** Dilution calculations, Supports mass/volume units, Supports weight/volume units, Ideal for labs and education, User-friendly interface

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

**In-app purchases:** none


### Locker

[App page](https://appshunter.io/ios/app/locker-password-manager/id1634798510)

Securely store and manage all your passwords and private information. Supports text, voice, drawings, and photos with high-strength encryption. Offers iCloud backup and restore for easy data recovery.

**Highlights:** Store text, voice, drawings, and photos, High-strength encryption, Import and export passwords, Gesture and fingerprint login, Random password generator, iCloud backup and restore, Data destruct feature

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

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 1-Month Plan | $1.49 | per month |
| 1-Quarter Plan | $2.99 | per 3 months |
| 1-Year Plan | $9.99 | per year |


## Frequently asked questions

### Is Solution Dilution Calculator free?

Solution Dilution Calculator costs $2.99, with no in-app purchases.

### Is Locker free?

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

### Which has better reviews, Solution Dilution Calculator or Locker?

Solution Dilution Calculator and Locker are both rated 5.0 out of 5 on the App Store, from 1 and 2 ratings respectively.

### Do Solution Dilution Calculator or Locker have ads?

Neither Solution Dilution Calculator nor Locker shows ads.

### Which is updated more often, Solution Dilution Calculator or Locker?

Solution Dilution Calculator ships an update every 22 months, and Locker every 3 weeks. Most recently, Solution Dilution Calculator was updated on September 10, 2026 and Locker on September 5, 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.*