i vs Arc+
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
i
This utility app assists machinists with CNC calculations, including cutting speed, RPM, and feed rate. It also provides databases for hole and shaft tolerances, as well as detailed thread specifications.
- Cutting speed calculation
- RPM calculation
- Feed rate calculation
- Hole and shaft tolerance database
- Thread data
- Milling, drilling, and turning operations
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iMachinist is a simple to use CNC calculator app that calculates for you the cuttings speed, RPM, feed rate and more for your milling, drilling and turning operations. iMachinist also includes a database for Hole and Shaft Tolerances and different Threads. Threads Data: - Outer Diameter (max/min) - Pitch Diameter (max/min) - Core Diameter (max/min) - Thread Height (max/min) Tolerance Data: - Zone (Shaft/Hole) - Grade (Shaft/Hole) - Diameter (Shaft/Hole) Cutting Calculator: - Tool Diameter - Cutting Speed - Spindle Speed - Number of Teeth - Feed per Tooth - Feed Rate
Arc+
This utility app helps users calculate various dimensions of circular arcs, including radius, length, width, and height. It offers a simple interface where users input two known values to derive the rest. Additional features include a unit converter, result saving, and sharing capabilities.
- Calculate Radius, Length, Width, Height, Tangent
- Input two known values to find others
- Measurement units converter
- Save results to favorites
- Share calculations
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Arc+ The Complete Circular Arc Calculator Calculates the Radius, Length, Width (chord), Height, Tangent How it works: Select two known values and type it in text boxes and click on ( = ) to get the required values. Features: Measurement units converter Save your results to a favorite list Share your results with others
Screenshots
Verdict
The clearest difference is rating: Arc+ at 4.6 against i's 2.6. Arc+ also leads on update cadence (every 4 months vs every 13 months) and review sentiment (50% vs 33%). i's advantage is in-app purchases (none vs 1). On price, ads, monetization model and iOS requirement there is nothing between them.
Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS
Both are free to download. Arc+ sells 1 one-off in-app purchase. i asks for nothing beyond the download.
Arc+ holds the better App Store score, 4.6 against 2.6. That said, the two scores are not equally well evidenced: Arc+ has 113 ratings behind it against 9, so its average is the more settled of the two. Written reviews point the same way: 33% of i's written reviews are positive against 50% of Arc+'s.
i ships an update every 13 months, Arc+ every 4 months. The most recent releases landed on October 3, 2026 and October 8, 2026 respectively.
| Parameter | i | Arc+ |
|---|---|---|
| Price | Free | Free |
| Rating | 2.6 (9 ratings) | 4.6 (113 ratings) — better |
| Positive reviews | 33.3% of reviews | 50.0% of reviews — better |
| Number of ratings | 9 | 113 — better |
| Update frequency | Every 13 months | Every 4 months — better |
| Ads | No | No |
| In-app purchases | No — better | Yes |
| Monetization | Free | Free |
| Devices | iPhone | iPhone, iPad, iPod — better |
| Requires iOS | 16.0 | 15.6 — better |
| Further details — not scored | ||
| Size | 8 MB | 4 MB |
| Age rating | 4+ | 4+ |
| Developer | ilan TETRUASHVILI | Mohamed Saad |
Customer experience
i
Arc+
In-app purchases
i
No in-app purchases
Arc+
- Ad Blocker$4.99
