# Mark Off vs Availability Sync

The clearest difference is in-app purchases: Availability Sync at none against Mark Off's 2. Availability Sync also leads on ads (none vs shown) and update cadence (weekly vs monthly). Mark Off's advantage is ratings volume (312 vs 5) and review sentiment (79% vs 67%). On price, rating, device support and iOS requirement there is nothing between them.

Both are free to download. Mark Off sells 2 in-app purchases, starting at $9.99 per year. Availability Sync asks for nothing beyond the download.

On the App Store both sit at effectively the same score — 4.5 for Mark Off against 4.4 for Availability Sync. That said, the two scores are not equally well evidenced: Mark Off has 312 ratings behind it against 5, so its average is the more settled of the two. Written reviews are what separate them: 79% of Mark Off's written reviews are positive against 67% of Availability Sync's.

Mark Off ships an update monthly, Availability Sync weekly. The most recent releases landed on September 17, 2026 and June 2, 2026 respectively.

## The numbers

| Metric | Mark Off | Availability Sync |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.5 (312 ratings)](https://appshunter.io/ios/app/mark-off-calendar-and-tracker/id1434848437/reviews)** | [4.4 (5 ratings)](https://appshunter.io/ios/app/availability-sync/id6670766226/reviews) |
| Number of ratings | **312** | 5 |
| Positive reviews | **79.1% of reviews** | 66.7% of reviews |
| In-app purchases | Yes | **No** |
| Ads | Yes | **No** |
| Update frequency | Monthly | **Weekly** |
| Monetization | Free with in-app purchases | **Free** |
| Size | 52 MB | 10 MB |
| Requires iOS | **16.0** | 17.5 |
| Devices | iPhone, iPad | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Viktor Gavrilov](https://appshunter.io/developer/1324295185) | [David Fuerst](https://appshunter.io/developer/1754806202) |

## What reviewers say

### Mark Off

[App page](https://appshunter.io/ios/app/mark-off-calendar-and-tracker/id1434848437)

Organize your life and visualize progress with a versatile calendar and tracker.  Create custom calendars for habits, travel, deadlines, work, and more, with visual progress tracking and customizable widgets.

**Highlights:** Multiple calendar types (habits, travel, deadlines, work), Streak tracking and statistics, Visual progress tracking, Customizable widgets, Add custom images to dates, Life journey visualization

**Features:** Family Sharing, Vision Pro support

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Mark Off Premium | $9.99 | per year |
| Lifetime - Premium | $49.99 | one-time |

**What reviewers like**

- 👍 Simple and intuitive interface
- ✅ Effective habit and streak tracking
- 🎨 Customizable colors and marking options
- 📱 Excellent home screen widgets
- 🔄 Reliable data sync and backup features

**What reviewers complain about**

- 🐛 Frequent data loss and deletion issues
- 🐛 App freezing and crashing problems
- 🐛 Widget functionality inconsistencies
- 🐛 Year view glitches and blank screens
- 📺 Excessive advertisements in free version

**Reported bugs**

- Data wiped after app updates
- App freezes when logging daily entries
- Widgets fail to load or update properly
- Year view displays blank/glitched
- Month calendar view not showing marked days

**Requested features**

- Desktop/web version with cloud sync
- Quick checkbox option without opening day details
- Streak counter widget display
- Ability to set past dates for life calendar chapters
- Improved setup and onboarding experience


### Availability Sync

[App page](https://appshunter.io/ios/app/availability-sync/id6670766226)

Easily share your free time slots for meetings and appointments. This app integrates with your existing calendars and allows for customized sharing messages and professional calendar invites. Streamline your scheduling process and avoid back-and-forth communication.

**Highlights:** Instant availability sharing, Calendar integration (iOS, Google, Outlook), Customizable sharing messages, Professional calendar invitations, Multiple time slot selection, Time zone management

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Mark Off free?

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

### Is Availability Sync free?

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

### Which has better reviews, Mark Off or Availability Sync?

Mark Off is rated higher. Mark Off averages 4.5 out of 5 from 312 ratings, while Availability Sync averages 4.4 from 5 ratings.

### Do Mark Off or Availability Sync have ads?

Mark Off shows ads; Availability Sync does not.

### Which is updated more often, Mark Off or Availability Sync?

Mark Off ships an update monthly, and Availability Sync weekly. Most recently, Mark Off was updated on September 17, 2026 and Availability Sync on June 2, 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.*