Comparison

NumLock vs Math Shield

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

Head to head
About

NumLock

Read full description

Your phone unlocks over 150 times a day. What if each unlock made you smarter? NumLock turns your screen time into brain time. Before you can open your blocked apps, solve a set of mental math problems. It takes seconds, keeps your mind sharp, and adds just enough friction to break the mindless scrolling habit. HOW IT WORKS Choose which apps to block. When you try to open one, NumLock presents math problems you solve on a number pad. Get them all right and your apps unlock for your chosen grace period. Simple, fast, and surprisingly satisfying. ADAPTIVE DIFFICULTY NumLock starts easy and gets harder as you improve. The 25-level system tracks your accuracy and speed, automatically adjusting to keep you challenged. Start with basic addition. Work your way up to multi-step equations, percentages, and large multiplication. You'll be amazed how fast your mental math improves. GRACE PERIODS THAT FIT YOUR LIFE After solving, your apps stay unlocked for a window you choose — 5 minutes for a quick check, 30 minutes for a balanced session, 1 hour for extended use, or until midnight for a full day off. When time's up, the lock comes back automatically. STREAKS AND STATS Build a daily streak by solving at least one session per day. Track your accuracy, average solve time, current level, and total problems solved. Watch yourself get faster and sharper over time. Your best streak is always recorded — can you beat it? DESIGNED FOR ADULTS NumLock isn't a parental control. It's a tool for people who want to take back control of their own screen time while training their brain. Think of it as a gym membership for your mind that activates every time you reach for a distraction. FEATURES — Block any app on your iPhone — Mental math challenges on a clean number pad — 25 levels of adaptive difficulty — Streak tracking with best-streak records — Accuracy and speed stats dashboard — Configurable grace periods (5 min to all day) — Light and dark mode — No ads, no data collection, fully private SUBSCRIPTION NumLock requires an active subscription to use. — Monthly: $4.99/month — Annual: $39.99/year (7-day free trial) Payment is charged to your Apple ID. Subscriptions auto-renew unless cancelled at least 24 hours before the end of the current period. Manage subscriptions in Settings → Apple ID → Subscriptions. Terms of Use (EULA): https://apptato.github.io/numlockapp/terms.html Privacy Policy: https://apptato.github.io/numlockapp/privacy.html

About

Math Shield

This app helps you reduce distractions by requiring you to solve a math problem before accessing blocked applications. It creates a barrier to break automatic habits and encourages more intentional screen time.

Highlights
  • Block distracting apps
  • Unlock with math challenges
  • Temporary app access
  • Reduce screen time
  • Build focus habits
  • Easy setup
Features
Read full description

Stay Focused with Math Shield Math Shield helps you reduce distractions and build better focus habits by placing a math challenge between you and your most distracting apps. Instead of mindlessly opening social media, games, or other time-wasting apps, you'll need to solve a math problem before gaining temporary access. This simple barrier helps break automatic habits and encourages intentional screen time. Key Features Block Distracting Apps: Choose the apps you want to limit and keep them locked during focus sessions. Unlock with Math Challenges: Solve math problems before accessing blocked apps. Temporary App Access: Gain limited access after successfully completing a challenge. Stay Productive: Create friction between impulses and distractions to help maintain focus. Easy Setup: Select apps, choose your preferences, and let Math Shield help you stay on track. Perfect For - Students who want to focus on studying - Professionals who need distraction-free work sessions - Anyone looking to reduce screen time - People building healthier digital habits Whether you're studying, working, reading, or spending time with family, Math Shield helps you take control of your attention—one challenge at a time. Download Math Shield and make every app unlock a conscious decision. To enjoy the full experience and to gain all the premium features, you can always purchase our Monthly, Yearly or Lifetime premium subscription pack. Math Shield will automatically charge your iTunes Account at the end of your subscription unless auto-renew is turned off at least 24 hours before the end of your current period. Subscriptions renew at the original price. You can turn off auto-renew at any time and still receive full functionality until the end of your current period, but no refund can be provided for unused portions of the subscription. Any unused portion of a free trial period, if offered, will be forfeited when the user purchases a subscription to that publication, where applicable. All your previous purchases can be easily restored using the **Restore Purchase** option in the app. This will provide you access to all the premium features. You can view Math Shield Terms of Use & Privacy Policy. Terms of Use (EULA):  https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ Privacy Policy: https://github.com/vinothvino42/app-privacy-policy/blob/main/math-shield.md

Screenshots

NumLock4 screens
Math Shield4 screens

Verdict

The call

The clearest difference is iOS requirement: NumLock at 17.0 against Math Shield's 26.0. 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. NumLock sells 2 in-app purchases, starting at $4.99 per month and Math Shield sells 3 in-app purchases, starting at $3.99 per month. Whichever you choose, the download price is not the number that matters.

Scorecard1 real difference · 8 level
NumLock versus Math Shield: the parameters behind the verdict, then further details
ParameterNumLockMath Shield
PriceFreeFree
Rating—1.0 (1 ratings) — better
Number of ratings—1 — better
Update frequency—Every 2 days
AdsNoNo
In-app purchasesYesYes
Monetization—Freemium
DevicesiPhoneiPhone
Requires iOS17.0 — better26.0
Further details — not scored
Size2 MB20 MB
Age rating4+4+
DeveloperPeter LiVinoth Ramajeyam

In-app purchases

2 purchases

NumLock

Subscriptions2
  • NumLock Pro Monthly$4.991 Month
  • NumLock Pro Annual7 Days trial$39.991 Year
3 purchases

Math Shield

Subscriptions2
  • Math Shield Pro Monthly$3.991 Month
  • Math Shield Pro Yearly3 Days trial$12.991 Year
One-time1
  • Math Shield Pro - Lifetime$19.99

Questions

Is NumLock free?
NumLock is free to download, with in-app purchases available.
Is Math Shield free?
Math Shield is free to download, with in-app purchases available.
Do NumLock or Math Shield have ads?
Neither NumLock nor Math Shield shows ads.

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