# Prod. Calc. for 1404 Lite vs Keystone

The clearest difference is update cadence: Keystone at fortnightly against Prod. Calc. for 1404 Lite's every 10 months. Prod. Calc. for 1404 Lite's advantage is device support (3 vs 1) and iOS requirement (12.0 vs 17.0). On price, ads and in-app purchases there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

Prod. Calc. for 1404 Lite ships an update every 10 months, Keystone fortnightly. The most recent releases landed on October 6, 2026 and October 24, 2026 respectively.

## The numbers

| Metric | Prod. Calc. for 1404 Lite | Keystone |
| --- | --- | --- |
| Price | Free | Free |
| Positive reviews | 0.0% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 10 months | **Fortnightly** |
| Monetization | Free | — |
| Size | 9 MB | 6 MB |
| Requires iOS | **12.0** | 17.0 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [Max Haertwig](https://appshunter.io/developer/494965291) | [Ionut Mocanu](https://appshunter.io/developer/1648541447) |

## What reviewers say

### Prod. Calc. for 1404 Lite

[App page](https://appshunter.io/ios/app/prod-calc-for-1404-lite/id553877830)

This app helps players optimize their city-building games by calculating the exact number and type of production buildings needed to support a given population. It visualizes production chains and building utilization, turning complex resource management into a simple, two-step process.

**Highlights:** Population input (inhabitants or houses), Results sorted by product, Building utilization display, Production chain visualization, Support for multiple building types per product

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

**In-app purchases:** none


### Keystone

[App page](https://appshunter.io/ios/app/keystone-project-tracker/id6760302143)

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

**In-app purchases:** none


## Frequently asked questions

### Is Prod. Calc. for 1404 Lite free?

Prod. Calc. for 1404 Lite is free to download, with no in-app purchases.

### Is Keystone free?

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

### Do Prod. Calc. for 1404 Lite or Keystone have ads?

Neither Prod. Calc. for 1404 Lite nor Keystone shows ads.

### Which is updated more often, Prod. Calc. for 1404 Lite or Keystone?

Prod. Calc. for 1404 Lite ships an update every 10 months, and Keystone fortnightly. Most recently, Prod. Calc. for 1404 Lite was updated on October 6, 2026 and Keystone 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.*