# CRSI Rebar Reference vs FRPRCS17

The clearest difference is in-app purchases: FRPRCS17 at none against CRSI Rebar Reference's 3. FRPRCS17 also leads on update cadence (every 2 weeks vs every 5 weeks) and iOS requirement (13.0 vs 15.1). CRSI Rebar Reference's advantage is device support. On price there is nothing between them.

Both are free to download. CRSI Rebar Reference sells 3 one-off in-app purchases. FRPRCS17 asks for nothing beyond the download.

CRSI Rebar Reference ships an update every 5 weeks, FRPRCS17 every 2 weeks. The most recent releases landed on October 4, 2026 and September 29, 2026 respectively.

## The numbers

| Metric | CRSI Rebar Reference | FRPRCS17 |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[3.3 (16 ratings)](https://appshunter.io/ios/app/crsi-rebar-reference/id1423271565/reviews)** | — |
| Number of ratings | **16** | — |
| Positive reviews | 33.3% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | No | — |
| Update frequency | Every 5 weeks | **Every 2 weeks** |
| Monetization | Free | — |
| Size | 51 MB | 17 MB |
| Requires iOS | 15.1 | **13.0** |
| Devices | **iPhone, iPad, iPod** | — |
| Age rating | 17+ | 4+ |
| Developer | [Concrete Reinforcing Steel Institute](https://appshunter.io/developer/1423271564) | [Poznan Supercomputing and Networking Center](https://appshunter.io/developer/726093818) |

## What reviewers say

### CRSI Rebar Reference

[App page](https://appshunter.io/ios/app/crsi-rebar-reference/id1423271565)

Access essential data for reinforcing bars (rebar) including specifications, hook details, and marking requirements. This app serves as a quick reference for industry standards and links to online resources.

**Highlights:** ASTM standard reinforcing bar specifications, Standard hook details (90, 135, 180 degrees), Stirrup/tie hook details, ASTM reinforcing bar marking requirements, Minimum yield and tensile requirements, Links to CRSI online resources

**Features:** macOS Compatibility

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| CRSI - Rebar Identifier Module | $2.99 | one-time |
| CRSI Development Length ACI | $4.99 | one-time |
| CRSI Development length AASHTO | $4.99 | one-time |


### FRPRCS17

[App page](https://appshunter.io/ios/app/frprcs17/id6781205585)

**In-app purchases:** none


## Frequently asked questions

### Is CRSI Rebar Reference free?

CRSI Rebar Reference is free to download, with in-app purchases available.

### Is FRPRCS17 free?

FRPRCS17 is free to download, with no in-app purchases.

### Which is updated more often, CRSI Rebar Reference or FRPRCS17?

CRSI Rebar Reference ships an update every 5 weeks, and FRPRCS17 every 2 weeks. Most recently, CRSI Rebar Reference was updated on October 4, 2026 and FRPRCS17 on September 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.*