# Plank Challenge vs 100 Sit

Plank Challenge and 100 Sit both sit at 4.7 stars, but that hides the real split: 88% of 100 Sit's written reviews are positive against 66% of Plank Challenge's. Plank Challenge's advantage is ratings volume (472 vs 139). On price, rating, update cadence and ads there is nothing between them.

Both are free to download. Plank Challenge sells 1 one-off in-app purchase and 100 Sit sells 2 in-app purchases, starting at $3.99 per month. Whichever you choose, the download price is not the number that matters.

On the App Store both sit at effectively the same score — 4.7 for Plank Challenge against 4.9 for 100 Sit. Both are backed by a comparable volume of ratings — 472 and 139 respectively. Written reviews are what separate them: 66% of Plank Challenge's written reviews are positive against 88% of 100 Sit's.

Plank Challenge ships an update every 3 weeks, 100 Sit every 2 weeks. Both last shipped on October 23, 2026.

## The numbers

| Metric | Plank Challenge | 100 Sit |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [4.7 (472 ratings)](https://appshunter.io/ios/app/plank-challenge-core-workout/id1083360252/reviews) | **[4.9 (139 ratings)](https://appshunter.io/ios/app/100-sit-ups-six-pack-trainer/id6466443313/reviews)** |
| Number of ratings | **472** | 139 |
| Positive reviews | 65.7% of reviews | **87.8% of reviews** |
| In-app purchases | Yes | Yes |
| Ads | Yes | Yes |
| Update frequency | Every 3 weeks | **Every 2 weeks** |
| Monetization | Free with in-app purchases | Free with in-app purchases |
| Size | 17 MB | 370 MB |
| Requires iOS | 16.0 | 16.0 |
| Devices | iPhone, iPad | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Bo Kalvslund](https://appshunter.io/developer/572272193) | [Foxyfitness GmbH](https://appshunter.io/developer/1658515547) |

## What reviewers say

### Plank Challenge

[App page](https://appshunter.io/ios/app/plank-challenge-core-workout/id1083360252)

This app guides you through a 5-week program to build up to a 4-minute plank. It requires no equipment and can be done in just 4 minutes daily, with rest days incorporated for recovery. It also includes a bonus push-up progression.

**Highlights:** 5-week structured plank program, Progressive push-up training, Daily workout instructions, Progress tracking, Apple Music integration, Distraction-free interface

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Plank Challenge Pro | $0.99 | one-time |

**What reviewers like**

- 👍 Simple and effective
- 💪 Great for plank challenges
- 🎯 Helps build stamina
- ✅ Good for beginners
- ✨ Straightforward design

**What reviewers complain about**

- 🔇 Music pauses during sets
- 🎵 Lack of in-app music/motivation
- ❓ No clear guidance on plank types
- 🎛️ No timer customization
- 👎 Push-up part lacks challenge

**Reported bugs**

- App crashes after iOS 13 update
- No times displayed after iOS 13 update
- Audio mutes automatically between active and rest
- App not running after iOS 13 update

**Requested features**

- Allow self-designed workouts
- Integrate reminders
- Add in-app music or motivational sounds
- Provide explanation on different plank types
- Include countdowns and motivational cues


### 100 Sit

[App page](https://appshunter.io/ios/app/100-sit-ups-six-pack-trainer/id6466443313)

This app acts as a personal fitness coach, using your device's motion sensor to automatically count sit-ups. It provides a structured training plan, voice coaching, and motivational features like leaderboards and streaks to help you achieve your core strength and abs goals.

**Highlights:** Automatic sit-up counting via motion sensor, Voice coaching for feedback, Global and friend leaderboards, Personalized training plans, Goal setting and reminders, Workout streaks tracking, Integration with Apple Health

**Features:** Vision Pro support

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Sit-Ups PRO | $3.99 | per month |
| Sit-Ups PRO | $19.99 | per year |

**What reviewers like**

- 👍 Motivates users to continue
- 👍 Reliable and trustworthy
- 👍 Fun and encouraging
- 👍 Good for home workouts
- 👍 Good motivation

**What reviewers complain about**

- 👎 Inaccurate counting
- 👎 Settings not intuitive
- 👎 Frequent premium upsells
- 👎 Usability issues on smartphones
- 👎 App becomes faulty after in-app purchase

**Reported bugs**

- Counts sit-ups inaccurately
- App freezes after in-app purchase
- Accidentally pay for premium due to screen sensitivity
- Pause ends too soon due to screen sensitivity

**Requested features**

- Allow filters to be set permanently
- Wish for a way to go back
- Language option for Russian
- Option to go back


## Frequently asked questions

### Is Plank Challenge free?

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

### Is 100 Sit free?

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

### Which has better reviews, Plank Challenge or 100 Sit?

100 Sit is rated higher. Plank Challenge averages 4.7 out of 5 from 472 ratings, while 100 Sit averages 4.9 from 139 ratings.

### Do Plank Challenge or 100 Sit have ads?

Both Plank Challenge and 100 Sit show ads.

### Which is updated more often, Plank Challenge or 100 Sit?

Plank Challenge ships an update every 3 weeks, and 100 Sit every 2 weeks. Most recently, Plank Challenge was updated on October 23, 2026 and 100 Sit on October 23, 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.*