# Grind75 vs Arc

The clearest difference is in-app purchases: Grind75 at none against Arc's 3. Arc's advantage is update cadence (every 9 days vs monthly). On price, review sentiment, ads and device support there is nothing between them.

Both are free to download. Arc sells 3 in-app purchases, starting at $2.99 per month. Grind75 asks for nothing beyond the download.

Grind75 ships an update monthly, Arc every 9 days. The most recent releases landed on November 9, 2026 and November 13, 2026 respectively.

## The numbers

| Metric | Grind75 | Arc |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.9 (55 ratings)](https://appshunter.io/ios/app/grind75/id6760317807/reviews)** | — |
| Number of ratings | **55** | — |
| Positive reviews | 100.0% of reviews | 100.0% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Monthly | **Every 9 days** |
| Monetization | **Free** | Freemium |
| Size | 21 MB | 18 MB |
| Requires iOS | 18.0 | **17.0** |
| Devices | iPhone, iPad | iPhone, Apple Watch |
| Age rating | 4+ | 4+ |
| Developer | [Priya Pappachen Yohannan](https://appshunter.io/developer/1883822079) | [岚烜 吴](https://appshunter.io/developer/6788589687) |

## What reviewers say

### Grind75

[App page](https://appshunter.io/ios/app/grind75/id6760317807)

This app helps you build discipline and stay consistent with self-improvement challenges like 75 Hard or 75 Soft. It offers flexible tracking for various habits, multiple challenge modes, and progress visualization to support your personal growth journey without rigid rules.

**Highlights:** Customizable challenge lengths, Multiple challenge modes (Hard, Medium, Soft, Parent), Habit tracking for fitness, water, reading, diet, and more, Progress photo and milestone tracking, Flexible system with pause and resume options, Health integration for step tracking, Shareable transformation cards

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

**In-app purchases:** none


### Arc

[App page](https://appshunter.io/ios/app/arc-75-day-challenge-tracker/id6796747380)

Track daily routines and build habits with customizable challenges. Integrates with Apple Health for automatic task completion. Offers a free starter challenge and optional Pro features for advanced tracking.

**Highlights:** Customizable challenge lengths (21-90 days), Apple Health auto-tracking integration, Strict mode for missed days, Finisher card with completion details, Home and lock screen widgets, No account required for privacy

**Features:** macOS Compatibility, Family Sharing, Apple Watch app, Vision Pro support

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Arc Pro Monthly | $2.99 | per month |
| Arc Pro Yearly | $19.99 | per year |
| Arc Pro | $29.99 | one-time |


## Frequently asked questions

### Is Grind75 free?

Grind75 is free to download, with no in-app purchases.

### Is Arc free?

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

### Do Grind75 or Arc have ads?

Neither Grind75 nor Arc shows ads.

### Which is updated more often, Grind75 or Arc?

Grind75 ships an update monthly, and Arc every 9 days. Most recently, Grind75 was updated on November 9, 2026 and Arc on November 13, 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.*