Comparison

0 vs Head Shadow AI

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

0

This app guides users through an 8-week program to build strength and stamina, aiming to achieve 200 situps. It offers voice cues, progress tracking, and community sharing features, with a free trial available.

Highlights
  • 8-week training program
  • Voice cues for guidance
  • Achieve badges and awards
  • Social media integration
  • Free trial period
  • Unlimited access with pass
Features
Read full description

■ Join the millions completing the Zen Challenge Series! ■ 0 to 200 Situps in 8 weeks! ■ Featured on Glamour Magazine, Yahoo!’s Appolicious, Popsugar Fitness, Apple’s “What’s Hot”, Apple’s “New & Noteworthy”, and doctor recommended on healthTap! "I've tried tons of different ab workouts, but this one was my favorite. It starts out easy to give you the confidence you need to keep going. Started only being able to do about 20 situps and week 2 is already 25, but the program breaks it into smaller sets and gives you rest breaks to build your stamina gradually. I'm now at 50 situps!" Are you ready for the 200 Situps Challenge? Train your body and build up to completing 200 situps with same people that brought you the OFFICIAL #1 5K Training app C25K®. Using a proven program, you will be able to complete 200 situps after just 8 weeks! The Zen Challenge Series is tailored towards all fitness levels. From first-timers to fitness veterans, this app will build up your strength and stamina to complete 200 situps. ≈ It's easy and straight forward to start ≈ 1. Just open the app and start! 2. Listen to the voice cues! ≈ Features ≈ ◎ First 2 weeks are free! Get started today! ◎ Achieve badges and awards for finishing a workout! ◎ Intuitive user friendly interface ◎ Integrated with Facebook/Twitter/Instagram communities, so share your progress and achievements! ≈ NEW Zen Unlimited Pass - Try it for free! ≈ ◉ Award winning music curated from top DJ's! ◉ Scientifically proven to increase motivation by 35% ◉ Unlimited access to all pro features across ALL Zen Labs Fitness apps We hope you enjoy the app and find it to be a useful training tool. Please leave us any friendly feedback, and rate us if you like the app! Questions/comments regarding the app? Please email us at contactus@zenlabsfitness.com or visit us at www.zenlabsfitness.com. ≈ Connect ≈ Facebook: @C25Kfree Twitter: @C25Kfree Instagram: @officialc25k Hashtag: #C25K https://forums.zenlabsfitness.com Subscription pricing and terms: The subscription will automatically renew unless turned off in your iTunes Account Settings at least 24 hours before current period ends. You can go to your iTunes Account settings to manage your subscription and turn off auto-renew. Your iTunes Account will be charged when the purchase is confirmed. If you subscribe before your free trial ends, the rest of your free trial period will be forfeited as soon as your purchase is confirmed. Privacy Policy & Terms of Use: https://www.zenlabsfitness.com/privacy-policy/ Legal Disclaimer This app and any information given by it or by Zen Labs Fitness are for educational purposes only. They are not intended nor implied to be a substitute for professional medical advice. You should always consult your healthcare provider before beginning any fitness program.

About

Head Shadow AI

Features
Read full description

Hear from your deaf side — without surgery Head Shadow AI is a hearing aid iPhone app that works like a CROS hearing aid for people with single-sided deafness (SSD). The app works best for people with SSD when used with a wired USB microphone and the iPhone speaker. Place the mic on your deaf side, about an arm’s length away from your mouth, and keep it out of direct line with the iPhone. The app captures sound with the mic, enhances it with digital signal processing, and plays it through the iPhone speaker placed close to you. This makes Head Shadow AI a non-surgical solution for people with SSD. No own voice. No delay. Placing the mic an arm’s length away from your mouth means there is no own voice. Since the audio is carried on a wire from the mic to the iPhone speaker, there is no delay. More comfortable listening Head Shadow AI can also be used with a wired USB microphone and AirPods Pro or compatible wireless earphones. The mic captures sound from your deaf side, while AirPods Pro or compatible earphones play the enhanced sound to your hearing ear. With the mic positioned away from your mouth, there is no own voice. Wireless earphones provide a more comfortable listening experience. Because wireless audio is used for playback, a small delay is present. This is the trade-off for the added comfort of using earphones. Built-in AI Head Shadow AI includes built-in AI that helps you understand how the app works and how its controls affect what you hear. A dedicated AI screen provides guided sections such as “How AI helps you” and “Using the app,” together with quick access to FAQs. Browse topics, view common questions, or search for specific help. AI guidance explains the Home screen, audio controls, and how digital signal processing affects what you hear. Most icons in the app are universally recognized. Where an icon needs explanation, an AI icon beside it provides quick access to help. Help available offline The app includes its help content for offline access, so you can use it even without an Internet connection. Simple to use Connect a wired USB microphone and place it on your deaf side, about an arm’s length away from your mouth. Choose the iPhone speaker or AirPods Pro or compatible wireless earphones for playback. Press Play. Private by design No recording. No storage. No data transmission. All audio processing happens locally on your iPhone, in real time. Pricing One-time purchase of $19.99. Includes a free trial. No subscription. No ongoing fees. Costs far less than traditional CROS hearing aid devices.

Screenshots

04 screens
Head Shadow AI3 screens

Verdict

The call

The clearest difference is update cadence: Head Shadow AI at every 4 weeks against 0's every 2 months. On price, ads, in-app purchases and device support 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

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. 0 sells 3 in-app purchases, starting at $4.99 per month and Head Shadow AI sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.

UpkeepUpdate frequency

0 ships an update every 2 months, Head Shadow AI every 4 weeks. The most recent releases landed on November 3, 2026 and October 31, 2026 respectively.

Scorecard1 real difference · 9 level
0 versus Head Shadow AI: the parameters behind the verdict, then further details
Parameter0Head Shadow AI
PriceFreeFree
Rating4.7 (2.1K ratings) — better—
Positive reviews58.9% of reviews—
Number of ratings2.1K — better—
Update frequencyEvery 2 monthsEvery 4 weeks — better
AdsNoNo
In-app purchasesYesYes
MonetizationFree with in-app purchases—
DevicesiPhone, iPad — betteriPhone
Requires iOS16.0 — better17.6
Further details — not scored
Size68 MB2 MB
Age rating4+4+
DeveloperZen LabsIsa Asudeh

Bugs and requests

0

Reported bugs

2 issues
  • Timer pauses when switching apps
  • Lack of background audio playback

Requested features

3 requests
  • Ability to adjust workout intensity and rest times
  • Option to skip warm-up
  • Workout progress tracking improvements

Head Shadow AI

Not enough reviews yet to summarise bugs or requests.

In-app purchases

3 purchases

0

Subscriptions3
  • Zen Unlimited Pass Monthly7 Days trial$4.991 Month
  • Zen Power Playlist 3 Months7 Days trial$29.993 Months
  • Zen Unlimited Pass Annual7 Days trial$74.991 Year
1 purchases

Head Shadow AI

One-time1
  • Full Access$19.99

Questions

Is 0 free?
0 is free to download, with in-app purchases available.
Is Head Shadow AI free?
Head Shadow AI is free to download, with in-app purchases available.
Do 0 or Head Shadow AI have ads?
Neither 0 nor Head Shadow AI shows ads.
Which is updated more often, 0 or Head Shadow AI?
0 ships an update every 2 months, and Head Shadow AI every 4 weeks. Most recently, 0 was updated on November 3, 2026 and Head Shadow AI on October 31, 2026.

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