# GTViewer vs EpochField 5.1

The clearest difference is review sentiment: GTViewer at 50% against EpochField 5.1's 0%. GTViewer also leads on rating (3.8 vs 1.0) and update cadence (fortnightly vs every 2 months). EpochField 5.1's advantage is iOS requirement (9.0 vs 17.0). On price, ratings volume, 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.

GTViewer holds the better App Store score, 3.8 against 1.0. Both are backed by a comparable volume of ratings — 4 and 2 respectively. Written reviews point the same way: 50% of GTViewer's written reviews are positive against 0% of EpochField 5.1's.

GTViewer ships an update fortnightly, EpochField 5.1 every 2 months. The most recent releases landed on October 29, 2026 and October 24, 2026 respectively.

## The numbers

| Metric | GTViewer | EpochField 5.1 |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[3.8 (4 ratings)](https://appshunter.io/ios/app/gtviewer/id905970171/reviews)** | [1.0 (2 ratings)](https://appshunter.io/ios/app/epochfield-51/id1582009280/reviews) |
| Number of ratings | **4** | 2 |
| Positive reviews | **50.0% of reviews** | 0.0% of reviews |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Fortnightly** | Every 2 months |
| Monetization | Free | Free |
| Size | 25 MB | 229 MB |
| Requires iOS | 17.0 | **9.0** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Graphic Technologies, Inc.](https://appshunter.io/developer/460458003) | [Epoch Solutions Group Inc](https://appshunter.io/developer/982576882) |

## What reviewers say

### GTViewer

[App page](https://appshunter.io/ios/app/gtviewer/id905970171)

This application allows users to download and view geospatial data on Apple devices without an internet connection. It functions similarly to a web-based counterpart but is designed for offline use.

**Highlights:** Offline geospatial data viewing, Downloadable data, Apple device compatibility, Geospatial data visualization

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

**In-app purchases:** none


### EpochField 5.1

[App page](https://appshunter.io/ios/app/epochfield-51/id1582009280)

This mobile mapping solution offers tools to streamline daily workflows for field workers. It allows for efficient download, visualization, and search of corporate GIS data, with offline functionality for 98% of its features. Navigate using on-board GPS and a library of basemaps.

**Highlights:** Streamline daily workflows, Download corporate GIS data, Visualize and search data, Offline functionality, On-board GPS navigation, Library of basemaps

**In-app purchases:** none


## Frequently asked questions

### Is GTViewer free?

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

### Is EpochField 5.1 free?

EpochField 5.1 is free to download, with no in-app purchases.

### Which has better reviews, GTViewer or EpochField 5.1?

GTViewer is rated higher. GTViewer averages 3.8 out of 5 from 4 ratings, while EpochField 5.1 averages 1.0 from 2 ratings.

### Do GTViewer or EpochField 5.1 have ads?

Neither GTViewer nor EpochField 5.1 shows ads.

### Which is updated more often, GTViewer or EpochField 5.1?

GTViewer ships an update fortnightly, and EpochField 5.1 every 2 months. Most recently, GTViewer was updated on October 29, 2026 and EpochField 5.1 on October 24, 2026.

---

*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*