# Topo Mobile vs GSD Drone Calculator

The clearest difference is in-app purchases: Topo Mobile at none against GSD Drone Calculator's 3. Topo Mobile also leads on ads (none vs shown) and iOS requirement (8.0 vs 18.6). GSD Drone Calculator's advantage is update cadence (monthly vs every 2 months). On price and device support there is nothing between them.

Both are free to download. GSD Drone Calculator sells 3 in-app purchases, starting at $1.99 per month. Topo Mobile asks for nothing beyond the download.

Topo Mobile ships an update every 2 months, GSD Drone Calculator monthly. The most recent releases landed on October 28, 2026 and October 24, 2026 respectively.

## The numbers

| Metric | Topo Mobile | GSD Drone Calculator |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[4.0 (3 ratings)](https://appshunter.io/ios/app/gsd-drone-calculator/id6450757319/reviews)** |
| Number of ratings | — | **3** |
| In-app purchases | **No** | Yes |
| Ads | **No** | Yes |
| Update frequency | Every 2 months | **Monthly** |
| Monetization | — | Free with in-app purchases |
| Size | 30 MB | 2 MB |
| Requires iOS | **8.0** | 18.6 |
| Devices | iPhone, iPod | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [SA PRESENCE](https://appshunter.io/developer/1056041008) | [Roman Akhromieiev](https://appshunter.io/developer/1223973006) |

## What reviewers say

### Topo Mobile

[App page](https://appshunter.io/ios/app/topo-mobile/id1085488342)

**Features:** macOS Compatibility

**In-app purchases:** none


### GSD Drone Calculator

[App page](https://appshunter.io/ios/app/gsd-drone-calculator/id6450757319)

Calculate Ground Sample Distance (GSD) for drone missions with this intuitive tool. Input drone specs and camera details to get precise GSD values for optimal mapping, surveying, and photography. Streamline your data collection and enhance accuracy for all aerial endeavors.

**Highlights:** Accurate GSD calculations, Input drone and camera specifications, Real-time GSD values, Optimize flight planning, Intuitive user interface, Save calculations, Image resolution insights

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

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Month | $1.99 | per month |
| Annual | $19.99 | per year |
| Lifetime | $29.99 | one-time |


## Frequently asked questions

### Is Topo Mobile free?

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

### Is GSD Drone Calculator free?

GSD Drone Calculator is free to download, with in-app purchases available.

### Do Topo Mobile or GSD Drone Calculator have ads?

GSD Drone Calculator shows ads; Topo Mobile does not.

### Which is updated more often, Topo Mobile or GSD Drone Calculator?

Topo Mobile ships an update every 2 months, and GSD Drone Calculator monthly. Most recently, Topo Mobile was updated on October 28, 2026 and GSD Drone Calculator 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.*