# Olyns vs Carbon Tracker US

The clearest difference is iOS requirement: Olyns at 12.4 against Carbon Tracker US's 18.5. On price, update cadence, 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.

Olyns ships an update every 5 weeks, Carbon Tracker US monthly. The most recent releases landed on October 16, 2026 and October 8, 2026 respectively.

## The numbers

| Metric | Olyns | Carbon Tracker US |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[3.8 (406 ratings)](https://appshunter.io/ios/app/olyns/id1495789093/reviews)** | — |
| Number of ratings | **406** | — |
| Positive reviews | 20.6% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 5 weeks | **Monthly** |
| Monetization | Free | — |
| Size | 37 MB | 4 MB |
| Requires iOS | **12.4** | 18.5 |
| Devices | iPhone, iPod | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Olyns Inc](https://appshunter.io/developer/1495789092) | [Siqin Yu](https://appshunter.io/developer/1836378162) |

## What reviewers say

### Olyns

[App page](https://appshunter.io/ios/app/olyns/id1495789093)

This app facilitates recycling by connecting users to a network of bottle boxes. Users can find nearby recycling locations, deposit beverage containers, and earn cash rewards redeemable via PayPal. It aims to make recycling convenient and rewarding while contributing to environmental sustainability.

**Highlights:** Find nearby recycling locations, Deposit beverage containers, Earn cash rewards, Save Olyns card to phone wallet, Touchless check-in via phone, Cash out via PayPal

**Features:** macOS Compatibility, Apple Wallet

**In-app purchases:** none

**What reviewers like**

- 🚀 Convenient recycling
- 💰 Instant cash payouts
- 🌎 Eco-friendly service

**What reviewers complain about**

- 🚨 Machines frequently full or broken
- ⏱️ Slow and time-consuming process
- 🤔 Inaccurate app information
- 🔍 Limited machine locations

**Reported bugs**

- Login/account verification issues
- Inconsistent container recognition
- Machines freezing/malfunctioning

**Requested features**

- Ability to favorite/track specific machine locations
- Real-time machine status updates
- Increase glass bottle capacity
- Expand operating hours


### Carbon Tracker US

[App page](https://appshunter.io/ios/app/carbon-tracker-us/id6751712815)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Olyns free?

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

### Is Carbon Tracker US free?

Carbon Tracker US is free to download, with no in-app purchases.

### Do Olyns or Carbon Tracker US have ads?

Neither Olyns nor Carbon Tracker US shows ads.

### Which is updated more often, Olyns or Carbon Tracker US?

Olyns ships an update every 5 weeks, and Carbon Tracker US monthly. Most recently, Olyns was updated on October 16, 2026 and Carbon Tracker US on October 8, 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.*