# NRG Optimizer vs Atomic Clock

The clearest difference is iOS requirement: NRG Optimizer at 12.0 against Atomic Clock's 15.1. On price, ads, in-app purchases and device support there is nothing between them.

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

## The numbers

| Metric | NRG Optimizer | Atomic Clock |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 13 months | — |
| Size | 154 MB | 29 MB |
| Requires iOS | **12.0** | 15.1 |
| Devices | iPhone, iPod | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [T.G.L. Inc.](https://appshunter.io/developer/1629823848) | [STAN I. C. ALEXANDRU PERSOANA FIZICA AUTORIZATA](https://appshunter.io/developer/1799569348) |

## What reviewers say

### NRG Optimizer

[App page](https://appshunter.io/ios/app/nrg-optimizer/id1629823846)

**Features:** macOS Compatibility

**In-app purchases:** none


### Atomic Clock

[App page](https://appshunter.io/ios/app/atomic-clock-exact-time/id6752546454)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is NRG Optimizer free?

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

### Is Atomic Clock free?

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

### Do NRG Optimizer or Atomic Clock have ads?

Neither NRG Optimizer nor Atomic Clock shows ads.

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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.*