# PA AIS Field Guide vs Shared Waters

The clearest difference is update cadence: Shared Waters at every 3 weeks against PA AIS Field Guide's every 5 months. PA AIS Field Guide's advantage is iOS requirement (12.0 vs 15.0). On price, ads, in-app purchases and device support there is nothing between them.

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

PA AIS Field Guide ships an update every 5 months, Shared Waters every 3 weeks. The most recent releases landed on October 20, 2026 and October 6, 2026 respectively.

## The numbers

| Metric | PA AIS Field Guide | Shared Waters |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (3 ratings)](https://appshunter.io/ios/app/pa-ais-field-guide/id1448504422/reviews)** | — |
| Number of ratings | **3** | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 5 months | **Every 3 weeks** |
| Monetization | Free | — |
| Size | 27 MB | 459 MB |
| Requires iOS | **12.0** | 15.0 |
| Devices | iPhone, iPod | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Skyward App Company](https://appshunter.io/developer/821096887) | [Stroud Water Research Center](https://appshunter.io/developer/1200990268) |

## What reviewers say

### PA AIS Field Guide

[App page](https://appshunter.io/ios/app/pa-ais-field-guide/id1448504422)

Identify, report, and catalog non-native aquatic animal and plant species in Pennsylvania. This educational tool helps users contribute to conservation efforts by documenting invasive species.

**Highlights:** Identify aquatic invasive species, Report sightings, Catalog species, Educational resource, Contribute to conservation

**Features:** macOS Compatibility

**In-app purchases:** none


### Shared Waters

[App page](https://appshunter.io/ios/app/shared-waters/id6759122772)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is PA AIS Field Guide free?

PA AIS Field Guide is free to download, with no in-app purchases.

### Is Shared Waters free?

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

### Do PA AIS Field Guide or Shared Waters have ads?

Neither PA AIS Field Guide nor Shared Waters shows ads.

### Which is updated more often, PA AIS Field Guide or Shared Waters?

PA AIS Field Guide ships an update every 5 months, and Shared Waters every 3 weeks. Most recently, PA AIS Field Guide was updated on October 20, 2026 and Shared Waters on October 6, 2026.

---

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