# CrimsonZip vs Shift by GSI

CrimsonZip and Shift by GSI are too close to call on the numbers: across 6 compared parameters — price, update cadence, ads and in-app purchases among them — neither pulls far enough ahead to decide it. What separates them is feature set and interface, not measurable difference.

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

CrimsonZip ships an update every 3 weeks, Shift by GSI every 11 days. The most recent releases landed on October 9, 2026 and October 28, 2026 respectively.

## The numbers

| Metric | CrimsonZip | Shift by GSI |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[5.0 (6 ratings)](https://appshunter.io/ios/app/shift-by-gsi/id6761119037/reviews)** |
| Number of ratings | — | **6** |
| Positive reviews | — | 100.0% of reviews |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 3 weeks | **Every 11 days** |
| Monetization | — | Free |
| Size | 54 MB | 61 MB |
| Requires iOS | 16.4 | **15.1** |
| Devices | iPhone | **iPhone, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Harvard University](https://appshunter.io/developer/382088726) | [Keith Anderson](https://appshunter.io/developer/1887871140) |

## What reviewers say

### CrimsonZip

[App page](https://appshunter.io/ios/app/crimsonzip/id6504200025)

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

**In-app purchases:** none


### Shift by GSI

[App page](https://appshunter.io/ios/app/shift-by-gsi/id6761119037)

Automatically track walks, bike rides, and transit trips to earn rewards and see your environmental impact. Stay motivated with streaks, badges, and community challenges. Discover new ways to get around and reduce your carbon footprint.

**Highlights:** Automatic trip detection (walk, bike, transit), Earn Shift Experience Points (XP), Local business rewards, Streaks and badges for motivation, Community leaderboards and challenges, Route suggestions and guides, School challenges for teachers

**In-app purchases:** none


## Frequently asked questions

### Is CrimsonZip free?

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

### Is Shift by GSI free?

Shift by GSI is free to download, with no in-app purchases.

### Do CrimsonZip or Shift by GSI have ads?

Neither CrimsonZip nor Shift by GSI shows ads.

### Which is updated more often, CrimsonZip or Shift by GSI?

CrimsonZip ships an update every 3 weeks, and Shift by GSI every 11 days. Most recently, CrimsonZip was updated on October 9, 2026 and Shift by GSI on October 28, 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.*