Lock In vs Heightly
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Lock In
This program guides users through a 75-day journey to build lasting confidence by establishing core habits. It leverages neuroscience to help users create daily evidence of their transformation, fostering self-trust and rewiring neural pathways for sustained change.
- 75-day habit program
- Neuroscience-based insights
- Daily evidence tracking
- Core commitment focus
- Supporting habit options
- Evening reflection prompts
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Tired of breaking promises to yourself? Struggling to trust you can actually change? Lock In offers a proven 75-day program to help you become someone who follows through. Built on neuroscience, not motivation, Lock In is your guide to building lasting confidence through daily evidence. How Lock In Works: 1. Choose Your Core Commitment Start by selecting 1-2 habits that matter most to you. These become your non-negotiables, the daily evidence that you're transforming. Add supporting habits to enhance your journey without the pressure of perfection. 2. Build Evidence Daily Each day, complete your core commitment to build your streak. Track your proof points and watch as 75 pieces of evidence accumulate into undeniable transformation. Miss a supporting habit? No problem. Your core commitment is what counts. 3. Daily Insights & Reflection Every morning, receive science-based insights explaining what's happening in your brain. Understand why day 12 feels hard, why week 3 has a dip, and how your neural pathways are rewiring. Reflect each evening on what you proved to yourself. Why 75 Days? Research shows it takes 66-90 days for your brain to update core beliefs about who you are. Lock In uses 75 days, long enough for real neural rewiring, short enough to maintain focus. By day 75, you won't need to believe in yourself, you'll have proof. Download Lock In now and take your first step towards a more fulfilling life. SUBSCRIPTION INFORMATION Full access to all features and the lock-in program is only available in the Lock In paid subscription plan (Monthly/Yearly). If you choose a Lock In Monthly/Yearly subscription, payment will be charged to iTunes Account at confirmation of purchase. The above mentioned content and features require a separate in-app purchase (Lock In Monthly/Yearly Subscription). The subscription will automatically renew unless turned off in your iTunes Account Settings at least 24 hours before the current period ends. From iTunes Account settings you can manage your subscription and turn off auto-renew. Your iTunes Account will be charged when the purchase is confirmed.
Heightly
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How tall will you be? Heightly turns that question into a plan. Answer a short quiz about your age, family height and lifestyle, and Heightly builds your personal height forecast using the same methods clinicians use: growth-chart data and the classic mid-parental formula, sharpened by your growth-stage signals. Then it gives you a daily program to make the most of the height that's still in your hands. YOUR FORECAST • A personal projected height that sharpens every week you track • See your percentile, your peak potential, and the odds of hitting your goal • Weekly height check-ins keep your prediction honest YOUR DAILY PLAN • Guided stretching and posture routines with a built-in timer • Daily goals for sleep, nutrition and training, with streaks that keep you showing up • Add your own custom goals AI MEAL SCANNER Snap a photo of any meal (or just describe it) and get an instant Growth Score with the protein, calcium and vitamin D that matter for growing bodies, plus one concrete way to make the meal better. AI GROWTH COACH Questions at 11pm about sleep, food or training? Your coach answers around the clock, personalised to your profile. SLEEP & NUTRITION TRACKING Log your nights and meals in seconds and watch your weekly analysis connect the dots between your habits and your growth. BUILT ON REAL RESEARCH Heightly's guidance draws on peer-reviewed studies on sleep, activity and nutrition in growing teens, and every study we cite in the app links to the original source so you can read it yourself. AN HONEST NOTE Genetics set most of your height. No app can promise extra centimetres, and anyone who does is guessing. What Heightly does is help you sleep, eat, move and stand like someone who reaches the top of their own range. SUBSCRIPTION DETAILS Heightly offers auto-renewing subscriptions (weekly or yearly) and a one-time lifetime purchase. Payment is charged to your Apple ID account at confirmation of purchase. Subscriptions renew automatically unless cancelled at least 24 hours before the end of the current period. Manage or cancel in your App Store account settings. Terms of Use: https://getheightly.com/terms Privacy Policy: https://getheightly.com/privacy
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Verdict
The clearest difference is iOS requirement: Heightly at 16.4 against Lock In's 18.0. On price, update cadence, ads and in-app purchases 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
Both are free to download. Lock In sells 2 in-app purchases, starting at $9.99 per month and Heightly sells 4 in-app purchases, starting at $5.99 per 7 days. Whichever you choose, the download price is not the number that matters.
Lock In ships an update every 2 weeks, Heightly every 3 weeks. The most recent releases landed on November 8, 2026 and November 5, 2026 respectively.
| Parameter | Lock In | Heightly |
|---|---|---|
| Price | Free | Free |
| Rating | 3.0 (6 ratings) — better | — |
| Positive reviews | 37.5% of reviews | — |
| Number of ratings | 6 — better | — |
| Update frequency | Every 2 weeks — better | Every 3 weeks |
| Ads | No | No |
| In-app purchases | Yes | Yes |
| Monetization | Free with in-app purchases | — |
| Devices | iPhone | iPhone |
| Requires iOS | 18.0 | 16.4 — better |
| Further details — not scored | ||
| Size | 11 MB | 65 MB |
| Age rating | 4+ | 12+ |
| Developer | MYLES NICHOLAS ROOT | zachary aaron frulloni |
In-app purchases
Lock In
- Lock-In Monthly Subscription$9.991 Month
- Lock In Yearly Subscription3 Days trial$29.991 Year
Heightly
- Weekly Plan$5.997 Days
- Yearly Plan Offer$6.991 Year
- Yearly Plan$34.991 Year
- Lifetime Access$34.99








