# R Discovery vs Calpy

The clearest difference is in-app purchases: Calpy at none against R Discovery's 6. Calpy also leads on update cadence (every 2 weeks vs monthly). R Discovery's advantage is device support (3 vs 1). On price, ads and iOS requirement there is nothing between them.

Both are free to download. R Discovery sells 6 in-app purchases, starting at $11.99 per month. Calpy asks for nothing beyond the download.

R Discovery ships an update monthly, Calpy every 2 weeks. The most recent releases landed on November 7, 2026 and November 10, 2026 respectively.

## The numbers

| Metric | R Discovery | Calpy |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.8 (926 ratings)](https://appshunter.io/ios/app/r-discovery-academic-research/id1508182175/reviews)** | — |
| Number of ratings | **926** | — |
| Positive reviews | 57.8% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | Monthly | **Every 2 weeks** |
| Monetization | Freemium | — |
| Size | 56 MB | 45 MB |
| Requires iOS | **15** | 16.4 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 17+ |
| Developer | [CACTUS COMMUNICATIONS SERVICES PTE. LTD](https://appshunter.io/developer/1817173784) | [EREN BAYHAN](https://appshunter.io/developer/6822076407) |

## What reviewers say

### R Discovery

[App page](https://appshunter.io/ios/app/r-discovery-academic-research/id1508182175)

Access and discover over 300 million research papers with AI-powered tools. Understand findings, chat with PDFs, and organize your academic library. Stay current in your field with personalized feeds and alerts.

**Highlights:** Discover 300M+ research papers, AI-powered research workflows, Chat with PDFs, Listen to research papers, Personalized research feeds, Organize academic library, Translate research papers

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

**In-app purchases (6)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Monthly | $11.99 | per month |
| Monthly | $24.99 | per month |
| Monthly | $25.00 | per month |
| Yearly | $69.00 | per year |
| Yearly | $139.99 | per year |
| Yearly | $143.99 | per year |

**What reviewers like**

- 👍 Wonderful site for research professionals
- 🚀 Fantastic app for researchers
- 💡 Provides relevant paper recommendations

**What reviewers complain about**

- 🐛 Slow and choppy performance
- 🐛 Buggy and unreliable features
- 🐛 Difficult to use certain core functions
- 🐛 Downloading PDFs doesn't work

**Reported bugs**

- Home screen takes a long time to load
- Audio translation feature doesn't work
- Buttons are extremely slow
- Switching between dark and light mode is glitchy

**Requested features**

- Add option to view author information in preview
- Enable screen rotation for iPad users
- Add more advanced search functionality
- Allow canceling of export in progress
- Improve integration with Zotero


### Calpy

[App page](https://appshunter.io/ios/app/calpy/id6822076405)

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

**In-app purchases:** none


## Frequently asked questions

### Is R Discovery free?

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

### Is Calpy free?

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

### Do R Discovery or Calpy have ads?

Neither R Discovery nor Calpy shows ads.

### Which is updated more often, R Discovery or Calpy?

R Discovery ships an update monthly, and Calpy every 2 weeks. Most recently, R Discovery was updated on November 7, 2026 and Calpy on November 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.*