# Portable Inventory vs Pendulum

The clearest difference is ratings volume: Portable Inventory at 220 against Pendulum's 16. Portable Inventory also leads on iOS requirement (13.0 vs 17.0). Pendulum's advantage is update cadence (every 9 days vs every 3 weeks). On price, rating, review sentiment and ads there is nothing between them.

Both are free to download. Portable Inventory sells 3 one-off in-app purchases and Pendulum sells 5 one-off in-app purchases. Whichever you choose, the download price is not the number that matters.

On the App Store both sit at effectively the same score — 4.1 for Portable Inventory against 4.2 for Pendulum. That said, the two scores are not equally well evidenced: Portable Inventory has 220 ratings behind it against 16, so its average is the more settled of the two. Written reviews are what separate them: 73% of Portable Inventory's written reviews are positive against 67% of Pendulum's.

Portable Inventory ships an update every 3 weeks, Pendulum every 9 days. The most recent releases landed on September 22, 2026 and September 10, 2026 respectively.

## The numbers

| Metric | Portable Inventory | Pendulum |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [4.1 (220 ratings)](https://appshunter.io/ios/app/portable-inventory/id1440455104/reviews) | **[4.2 (16 ratings)](https://appshunter.io/ios/app/pendulum-pen-pal-tracker/id6444290573/reviews)** |
| Number of ratings | **220** | 16 |
| Positive reviews | **72.6% of reviews** | 66.7% of reviews |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | Every 3 weeks | **Every 9 days** |
| Monetization | Free with in-app purchases | Free with in-app purchases |
| Size | 4 MB | 5 MB |
| Requires iOS | **13.0** | 17.0 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Chengdu Wangqi03 Technology Ltd.](https://appshunter.io/developer/706772908) | [Benjamin Cardy](https://appshunter.io/developer/1588708175) |

## What reviewers say

### Portable Inventory

[App page](https://appshunter.io/ios/app/portable-inventory/id1440455104)

Easily track the quantity of any items, from personal belongings to business inventory. Set warning levels and organize items into groups for quick visual identification. Monitor item changes and view detailed statistics and rankings.

**Highlights:** Track item counts, Set warning levels, Organize items by groups, Visual item status indicators, View item statistics and rankings, Change log for items and groups, iCloud synchronization

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

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Complete Version | $1.99 | one-time |
| Pro Version | $7.29 | one-time |
| Pro Version | $9.99 | one-time |

**What reviewers like**

- 👍 Simple and easy to use
- 🚀 Efficient inventory tracking
- 💡 Customizable color coding
- 👍 Clean and intuitive UI

**What reviewers complain about**

- 🐛 Occasional crashes and data loss
- 🔀 Difficulty in reorganizing inventory
- 💡 Limited color options
- 🔀 Issues with syncing across devices

**Reported bugs**

- Inventory counts resetting to zero unexpectedly
- Inability to edit item names after creation
- Issues with importing large inventory lists

**Requested features**

- Add photo support for inventory items
- Ability to set minimum stock levels
- Option to sort and rearrange inventory lists
- Implement a reset function to reset all counts to zero
- Add push notifications for low stock items


### Pendulum

[App page](https://appshunter.io/ios/app/pendulum-pen-pal-tracker/id6444290573)

This app helps you manage your pen pal relationships by tracking correspondence. Record when you send and receive letters, note writing materials, and set reminders to stay in touch. Sync your data across devices for seamless management.

**Highlights:** Track sent and received letters, Record pen, ink, and paper used, Set reminders to write and post, Monitor letter delivery times, iCloud sync across devices

**In-app purchases (5)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Extra Fine Tip | $0.99 | one-time |
| Fine Tip | $1.99 | one-time |
| Medium Tip | $3.99 | one-time |
| Broad Tip | $5.99 | one-time |
| Stub Tip | $9.99 | one-time |


## Frequently asked questions

### Is Portable Inventory free?

Portable Inventory is free to download, with in-app purchases available.

### Is Pendulum free?

Pendulum is free to download, with in-app purchases available.

### Which has better reviews, Portable Inventory or Pendulum?

Pendulum is rated higher. Portable Inventory averages 4.1 out of 5 from 220 ratings, while Pendulum averages 4.2 from 16 ratings.

### Do Portable Inventory or Pendulum have ads?

Neither Portable Inventory nor Pendulum shows ads.

### Which is updated more often, Portable Inventory or Pendulum?

Portable Inventory ships an update every 3 weeks, and Pendulum every 9 days. Most recently, Portable Inventory was updated on September 22, 2026 and Pendulum on September 10, 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.*