# Dos Notes vs Blackout Math.Power Calculator

The clearest difference is price: Blackout Math.Power Calculator at Free against Dos Notes's $4.99. Dos Notes's advantage is in-app purchases (none vs 1) and iOS requirement (16.4 vs 18). On update cadence, ads and device support there is nothing between them.

Blackout Math.Power Calculator is free to download; Dos Notes costs $4.99 up front. Blackout Math.Power Calculator sells 1 one-off in-app purchase. Dos Notes asks for nothing beyond the download.

Dos Notes ships an update every 5 days, Blackout Math.Power Calculator every 6 days. The most recent releases landed on September 8, 2026 and June 7, 2026 respectively.

## The numbers

| Metric | Dos Notes | Blackout Math.Power Calculator |
| --- | --- | --- |
| Price | $4.99 | **Free** |
| Rating | — | **[3.0 (5 ratings)](https://appshunter.io/ios/app/blackout-mathpower-calculator/id6755345214/reviews)** |
| Number of ratings | — | **5** |
| Positive reviews | — | 0.0% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | **Every 5 days** | Every 6 days |
| Monetization | — | Free |
| Size | 14 MB | 10 MB |
| Requires iOS | **16.4** | 18 |
| Devices | iPhone, iPad | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Denis Kashin](https://appshunter.io/developer/1140100282) | [Yevheniia Borunova](https://appshunter.io/developer/1684316852) |

## What reviewers say

### Dos Notes

[App page](https://appshunter.io/ios/app/dos-notes/id6754763351)

**Features:** macOS Compatibility

**In-app purchases:** none


### Blackout Math.Power Calculator

[App page](https://appshunter.io/ios/app/blackout-mathpower-calculator/id6755345214)

This app helps you accurately calculate power outage durations and battery performance. It factors in real-world conditions like battery discharge, inverter efficiency, and device consumption to provide realistic estimates for runtime and charging.

**Highlights:** Calculate usable battery energy (Wh/kWh), Factor in safe depth of discharge, Account for inverter efficiency and losses, Calculate real device energy consumption, Estimate actual device runtime, Provide accurate battery charging time estimates, Explain complex energy concepts clearly

**Features:** macOS Compatibility

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Full Access | $2.99 | one-time |


## Frequently asked questions

### Is Dos Notes free?

Dos Notes costs $4.99, with no in-app purchases.

### Is Blackout Math.Power Calculator free?

Blackout Math.Power Calculator is free to download, with in-app purchases available.

### Do Dos Notes or Blackout Math.Power Calculator have ads?

Neither Dos Notes nor Blackout Math.Power Calculator shows ads.

### Which is updated more often, Dos Notes or Blackout Math.Power Calculator?

Dos Notes ships an update every 5 days, and Blackout Math.Power Calculator every 6 days. Most recently, Dos Notes was updated on September 8, 2026 and Blackout Math.Power Calculator on June 7, 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.*