# ISO Today vs TVA Energy Data

The clearest difference is rating: TVA Energy Data at 5.0 against ISO Today's 4.2. TVA Energy Data also leads on review sentiment (100% vs 74%). ISO Today's advantage is ratings volume (103 vs 3). On price, update cadence, 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.

TVA Energy Data holds the better App Store score, 5.0 against 4.2. That said, the two scores are not equally well evidenced: ISO Today has 103 ratings behind it against 3, so its average is the more settled of the two. Written reviews point the same way: 74% of ISO Today's written reviews are positive against 100% of TVA Energy Data's.

ISO Today ships an update every 3 months, TVA Energy Data every 6 months. The most recent releases landed on October 23, 2026 and October 18, 2026 respectively.

## The numbers

| Metric | ISO Today | TVA Energy Data |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [4.2 (103 ratings)](https://appshunter.io/ios/app/iso-today/id596881268/reviews) | **[5.0 (3 ratings)](https://appshunter.io/ios/app/tva-energy-data/id1024744472/reviews)** |
| Number of ratings | **103** | 3 |
| Positive reviews | 74.1% of reviews | **100.0% of reviews** |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 3 months** | Every 6 months |
| Monetization | Free | Free |
| Size | 11 MB | 26 MB |
| Requires iOS | 13.0 | 13.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [California Independent System Operator Corporation](https://appshunter.io/developer/596881471) | [Tennessee Valley Authority](https://appshunter.io/developer/440331546) |

## What reviewers say

### ISO Today

[App page](https://appshunter.io/ios/app/iso-today/id596881268)

Track California's power grid status, energy prices, and renewable production. Receive alerts for conservation needs and monitor supply adequacy up to seven days ahead. View detailed supply breakdowns and historical data.

**Highlights:** Monitor resource adequacy capacity, View grid status and demand, Renewables and supply graphs, Wholesale energy price map, Receive Flex Alerts, Track calendar events

**Features:** macOS Compatibility

**In-app purchases:** none

**What reviewers like**

- 💡 Informative data about grid
- 👍 Easy to use interface
- 📊 Nice graphs and visuals
- 🚀 Fast loading (in some reviews)
- ✅ Good for energy consumers

**What reviewers complain about**

- 🐛 Crashes frequently
- ⚠️ Alerts not clearing
- 📩 Too many duplicate alerts
- 🐌 Slow loading times
- 📱 Text size too small

**Reported bugs**

- App crashes on launch
- Calendar crashes instantly
- Alerts cannot be cleared
- Page does not scroll properly with alerts
- Items below Calendar unreachable on smaller screens

**Requested features**

- Localized alerts
- Ability to turn on/off alerts for specific locales
- Multi-day and seasonal trends
- Home-screen widget
- See today's demand vs. last year/week


### TVA Energy Data

[App page](https://appshunter.io/ios/app/tva-energy-data/id1024744472)

Access near real-time and historical energy usage data, demand information, and power system alerts. This app requires authorized access and is designed for TVA's directly served customers needing on-the-go information.

**Highlights:** Near real-time energy data, Current day interval data, Month-to-date usage and demand, Historical energy and demand, Power system alerts, TVA key contacts

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is ISO Today free?

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

### Is TVA Energy Data free?

TVA Energy Data is free to download, with no in-app purchases.

### Which has better reviews, ISO Today or TVA Energy Data?

TVA Energy Data is rated higher. ISO Today averages 4.2 out of 5 from 103 ratings, while TVA Energy Data averages 5.0 from 3 ratings.

### Do ISO Today or TVA Energy Data have ads?

Neither ISO Today nor TVA Energy Data shows ads.

### Which is updated more often, ISO Today or TVA Energy Data?

ISO Today ships an update every 3 months, and TVA Energy Data every 6 months. Most recently, ISO Today was updated on October 23, 2026 and TVA Energy Data on October 18, 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.*