# Mercury vs Little Green Button

The clearest difference is review sentiment: Little Green Button at 100% against Mercury's 0%. Mercury's advantage is in-app purchases (none vs 1) and iOS requirement (8.0 vs 15.6). On price, update cadence, ads and device support there is nothing between them.

Both are free to download. Little Green Button sells 1 in-app purchase, starting at $204.99 per year. Mercury asks for nothing beyond the download.

Mercury ships an update every 3 months, Little Green Button every 2 months. The most recent releases landed on October 4, 2026 and October 29, 2026 respectively.

## The numbers

| Metric | Mercury | Little Green Button |
| --- | --- | --- |
| Price | Free | Free |
| Positive reviews | 0.0% of reviews | **100.0% of reviews** |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 3 months | **Every 2 months** |
| Monetization | **Free** | Subscription |
| Size | 20 MB | 60 MB |
| Requires iOS | **8.0** | 15.6 |
| Devices | iPhone, iPod | **iPhone, iPad, iPod** |
| Age rating | 4+ | 17+ |
| Developer | [R Hamilton & Co Ltd.](https://appshunter.io/developer/482574203) | [Little Green Button Limited](https://appshunter.io/developer/1509411090) |

## What reviewers say

### Mercury

[App page](https://appshunter.io/ios/app/mercury/id482574198)

Control your multi-room audio system remotely. Manage playback, zones, and settings for a seamless listening experience throughout your home.

**Highlights:** Remote control, Multi-room audio system management, Zone control, Playback management, Settings adjustment

**Features:** macOS Compatibility

**In-app purchases:** none


### Little Green Button

[App page](https://appshunter.io/ios/app/little-green-button/id1509411091)

This safety companion app acts as a panic button and duress alarm system. It allows users to share alerts with a response group and provides access to a management site for managing subscriptions and user keys.

**Highlights:** Panic button functionality, Duress alarm system, Share alerts with response group, Access to management site, Auto-renewable subscription, Supports up to 4 additional users

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Annual Subscription (Seed) | $204.99 | per year |


## Frequently asked questions

### Is Mercury free?

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

### Is Little Green Button free?

Little Green Button is free to download, with in-app purchases available.

### Do Mercury or Little Green Button have ads?

Neither Mercury nor Little Green Button shows ads.

### Which is updated more often, Mercury or Little Green Button?

Mercury ships an update every 3 months, and Little Green Button every 2 months. Most recently, Mercury was updated on October 4, 2026 and Little Green Button on October 29, 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.*