# uSpectrum PAR vs Grow Guide

The clearest difference is rating: Grow Guide at 4.9 against uSpectrum PAR's 1.0. Grow Guide also leads on update cadence (weekly vs every 8 months) and ratings volume (126 vs 2). uSpectrum PAR's advantage is in-app purchases (none vs 3) and iOS requirement (9.0 vs 15.0). On price, ads and device support there is nothing between them.

Both are free to download. Grow Guide sells 3 in-app purchases, starting at $5.99 per month. uSpectrum PAR asks for nothing beyond the download.

Grow Guide holds the better App Store score, 4.9 against 1.0. That said, the two scores are not equally well evidenced: Grow Guide has 126 ratings behind it against 2, so its average is the more settled of the two.

uSpectrum PAR ships an update every 8 months, Grow Guide weekly. The most recent releases landed on September 16, 2026 and October 15, 2026 respectively.

## The numbers

| Metric | uSpectrum PAR | Grow Guide |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [1.0 (2 ratings)](https://appshunter.io/ios/app/uspectrum-par/id1466017397/reviews) | **[4.9 (126 ratings)](https://appshunter.io/ios/app/grow-guide/id6637720578/reviews)** |
| Number of ratings | 2 | **126** |
| Positive reviews | — | 96.7% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 8 months | **Weekly** |
| Monetization | **Free** | Free with in-app purchases |
| Size | 25 MB | 85 MB |
| Requires iOS | **9.0** | 15.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 17+ |
| Developer | [United Power Research Technology Corporation](https://appshunter.io/developer/1501316337) | [phannafest llc](https://appshunter.io/developer/1209901791) |

## What reviewers say

### uSpectrum PAR

[App page](https://appshunter.io/ios/app/uspectrum-par/id1466017397)

This application connects wirelessly to a handheld spectral PAR meter, allowing remote analysis and configuration of light sources. It displays detailed spectral data, light source information, and absorption metrics, with options to save and share measurements.

**Highlights:** Wireless Bluetooth connection, Remote light source analysis, Save captured data, Display spectrum and CIE diagrams, View light source metrics (LUX, CCT, CRI), Share measured data via email

**Features:** macOS Compatibility

**In-app purchases:** none


### Grow Guide

[App page](https://appshunter.io/ios/app/grow-guide/id6637720578)

This app helps users track their cannabis grows from seed to harvest. It offers AI-powered advice, a community forum for knowledge sharing, and professional tools like a VPD calculator and light meter. Create time-lapse videos of your plants and learn from experienced cultivators.

**Highlights:** Daily grow tracking journal, AI-powered plant advice, Time-lapse video creation, Active grower community, Professional growing tools (VPD, light meter), Nutrient and environment tracking

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

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Grow Guide Pro | $5.99 | per month |
| Grow Guide Pro | $39.99 | per year |
| Grow Guide Pro (LTD) | $149.00 | one-time |


## Frequently asked questions

### Is uSpectrum PAR free?

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

### Is Grow Guide free?

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

### Which has better reviews, uSpectrum PAR or Grow Guide?

Grow Guide is rated higher. uSpectrum PAR averages 1.0 out of 5 from 2 ratings, while Grow Guide averages 4.9 from 126 ratings.

### Do uSpectrum PAR or Grow Guide have ads?

Neither uSpectrum PAR nor Grow Guide shows ads.

### Which is updated more often, uSpectrum PAR or Grow Guide?

uSpectrum PAR ships an update every 8 months, and Grow Guide weekly. Most recently, uSpectrum PAR was updated on September 16, 2026 and Grow Guide on October 15, 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.*