# Watt Advisor vs MillBook

The clearest difference is in-app purchases: Watt Advisor at none against MillBook's 6. Watt Advisor also leads on iOS requirement (13.4 vs 15.0). On price, update cadence, ads and device support there is nothing between them.

Both are free to download. MillBook sells 6 in-app purchases, starting at $1.99 per month. Watt Advisor asks for nothing beyond the download.

Watt Advisor ships an update every 6 weeks, MillBook monthly. The most recent releases landed on October 30, 2026 and October 31, 2026 respectively.

## The numbers

| Metric | Watt Advisor | MillBook |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (1 ratings)](https://appshunter.io/ios/app/watt-advisor/id6608980277/reviews)** | — |
| Number of ratings | **1** | — |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 6 weeks | **Monthly** |
| Monetization | Free | — |
| Size | 34 MB | 51 MB |
| Requires iOS | **13.4** | 15.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [BreakSmart LLC](https://appshunter.io/developer/1761164384) | [halit aldemir](https://appshunter.io/developer/1852616652) |

## What reviewers say

### Watt Advisor

[App page](https://appshunter.io/ios/app/watt-advisor/id6608980277)

This app analyzes your energy usage to provide personalized advice on solar installation, energy plans, and home efficiency. It also monitors grid conditions and sends alerts for potential reliability issues. Optimize your energy consumption and save money with smart recommendations.

**Highlights:** Energy usage analysis, Solar calculator, Grid reliability alerts, Energy contract analysis, Home energy efficiency assessment, Smart device optimization

**Features:** macOS Compatibility

**In-app purchases:** none


### MillBook

[App page](https://appshunter.io/ios/app/millbook-rice-mill-log/id6779968788)

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

**In-app purchases (6)**

| Purchase | Price | Billing |
| --- | --- | --- |
| MillBook Pro (Monthly) | $1.99 | per month |
| MillBook Pro (Monthly) | $2.99 | per month |
| MillBook Pro (Yearly) | $19.99 | per year |
| MillBook Pro (Yearly) | $29.99 | per year |
| MillBook Pro (Lifetime) | $29.99 | one-time |
| MillBook Pro (Lifetime) | $49.99 | one-time |


## Frequently asked questions

### Is Watt Advisor free?

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

### Is MillBook free?

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

### Do Watt Advisor or MillBook have ads?

Neither Watt Advisor nor MillBook shows ads.

### Which is updated more often, Watt Advisor or MillBook?

Watt Advisor ships an update every 6 weeks, and MillBook monthly. Most recently, Watt Advisor was updated on October 30, 2026 and MillBook on October 31, 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.*