Comparison

RacketLog vs String Tension AI

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

Head to head
About

RacketLog

Features
Read full description

RacketLog takes the guesswork out of restringing. Track how long your strings have been in, how many hours you've played on them, and get notified when it's time for a fresh set. Whether you play twice a week or every day, RacketLog keeps your setup dialled in so your strings never hold you back. HOW IT WORKS RacketLog tracks string wear using two factors: play time and string age. Strings lose tension and feel over time, even when you're not playing. RacketLog monitors both and warns you when either limit is reached — whichever comes first. You set the targets. RacketLog does the rest. QUICK SESSION LOGGING Log play time in one tap from the home screen. Choose from preset durations or enter a custom session with date, duration, type (practice or match), court surface, and notes. Set your preferred defaults so every quick log matches how you actually play. STRING JOB TRACKING Record every restring with full details — brand, model, gauge, material, tension, stringer, colour, and cost. Set up a full bed or hybrid with separate mains and crosses. When you restring, copy your previous setup with one tap. Rate each string job across seven categories: durability, control, power, spin, comfort, feel, and appearance. Over time, your ratings help you find the string that suits your game. SMART WEAR TRACKING A visual gauge on every racket card shows remaining string life at a glance. Four status levels keep you informed: • Healthy — strings are fresh • Heads-up — approaching your target • Replace soon — time to book a restring • Overdue — past your recommended limit Targets are fully customisable by string material. Poly, multifilament, synthetic gut, and natural gut each have their own defaults, and you can adjust them to match your feel. BUILT-IN CATALOGS Choose from preset lists of major racket and string brands. String selection automatically detects the material type. Searchable pickers make setup fast, and manual entry is always available. RACKET MANAGEMENT Store your racket details — brand, model, grip size, string pattern, purchase date, price, and notes. Add a photo from your camera or library. Archive rackets you're no longer using to keep a clean home screen without losing any history. STATISTICS & INSIGHTS View stats across all rackets or drill into one. See total play time, session counts, match and practice splits, your most active day, longest weekly streak, and a month-by-month activity breakdown. Track total spending, average cost per restring, and cost per hour of play. NOTIFICATIONS Get push notifications when your strings reach heads-up, replace soon, or overdue status. Never get caught with dead strings before a match. BACKUP & EXPORT Export all your data as a readable JSON file. Save it to Files, iCloud Drive, or any cloud service for safekeeping. FREE & PREMIUM Track one racket with every feature — completely free. Upgrade to Premium for unlimited rackets. Download RacketLog and take control of your string setup. Legal: • Privacy Policy: https://www.frearbroslabsusa.com/racketlog-privacy.html • Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

About

String Tension AI

This app uses your iPhone's microphone to measure the tension of your racquet strings. It tracks tension decay over time, offers personalized restring recommendations, and provides a comprehensive string toolkit for serious players.

Highlights
  • Measure string tension with iPhone microphone
  • Track tension decay over time
  • Personalized restring recommendations
  • String database and player setups
  • Playing session tracking
  • Cost tracking for restringing
Features
Read full description

Know when your strings are losing their edge - before you feel it on court. String Tension AI turns a tap on your stringbed into a tension reading you can track. Use your iPhone's microphone to follow tension loss, understand each string job, and make better restringing decisions. No external hardware required. MEASURE WITH CONFIDENCE • Get a tension reading by tapping the center of your strings near your iPhone • Follow real-time quality coaching for clearer, more repeatable measurements • Calibrate against a known reference tension for a stronger baseline • Unlock PRO Measurement Insights that help improve your technique • Audio is processed on your device and is never recorded, stored, or uploaded KNOW WHEN IT IS TIME TO RESTRING • See String Health at a glance: Fresh, Good, Fading, or Restring soon • Follow tension-decay charts and the readings behind them • Get smart restring guidance based on your own trustworthy measurement history • With PRO, set tension targets and optional alerts when your strings move outside range • With PRO, let Smart Detection recognize likely fresh strings or unusual tension changes LEARN WHAT WORKS FOR YOUR GAME • With PRO, compare racquets, strings, and completed string jobs side by side • Analyze tension retention across multiple string jobs with PRO—not just the latest one • Use PRO Tension Advisor to explore a better tension for your equipment, game, and conditions • Get PRO string and hybrid recommendations matched to your playstyle, ratings, and qualified tension-retention history • Build and track full beds, hybrids, custom string models, and two-sided setups ASK STRING AI COACH On compatible devices, String AI Coach answers questions about your racquet, strings, tension, playing history, restring timing, and costs using your saved data. It runs with Apple's on-device model; your questions, answers, and racquet data are not uploaded. Requires iOS 26 or later, a supported locale, and an available on-device model. Some questions require PRO. CONNECT PLAYING TIME TO STRING LIFE • Log sessions with duration, racquet, and intensity • Review your month on a Playing Sessions calendar, including restring days • Build streaks and goals, celebrate milestone unlocks and rank-ups, and share milestone cards. PRO adds the gallery, nudges, and alerts. • With PRO, see how playing volume affects tension retention and cost per playing hour YOUR COMPLETE RACQUET AND STRING TOOLKIT • Explore detailed string and racquet catalogs plus ATP, WTA, and Legends setups • Save favorite strings and rate what you have played; build a wishlist with PRO • With PRO, track stringers, restring costs, annual budgets, and retired setups • Create visual Share Cards for String Health, tension history, string jobs, milestones, streaks, and eligible cost insights • With PRO, export PDF and CSV reports, including string-job reports for your stringer • Import, inspect, and restore backups with clear safeguards • Keep PRO data in sync across your Apple devices with iCloud Built for smooth performance with large histories, VoiceOver, Dynamic Type, and Reduce Motion. FREE VS PRO Free includes unlimited measurements for one racquet, your 20 most recent readings, quality coaching, calibration, String Health, session logging, goals, daily measurement tips, supported Share Cards, supported String AI Coach questions, and the string, racquet, and pro-player databases. PRO unlocks unlimited racquets and string setups, full measurement history, advanced decay and comparison analytics, personalized string and hybrid recommendations, Tension Advisor, tension targets and advanced reminders, detailed playing and cost analytics, advanced milestone features, wishlist and stringer tools, advanced String AI Coach questions, iCloud sync, and PDF/CSV export. Measure today. Learn from every session. Restring with confidence. Terms of Use: https://stringtensionai.com/terms/ Privacy Policy: https://stringtensionai.com/privacy/

Screenshots

RacketLog4 screens
String Tension AI4 screens

Verdict

The call

The clearest difference is update cadence: RacketLog at daily against String Tension AI's every 5 days. 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. RacketLog sells 1 in-app purchase, starting at $14.99 per year and String Tension AI sells 3 in-app purchases, starting at $4.99 per month. Whichever you choose, the download price is not the number that matters.

UpkeepUpdate frequency

RacketLog ships an update daily, String Tension AI every 5 days. The most recent releases landed on August 20, 2026 and September 23, 2026 respectively.

Scorecard1 real difference · 9 level
RacketLog versus String Tension AI: the parameters behind the verdict, then further details
ParameterRacketLogString Tension AI
PriceFreeFree
Rating—5.0 (2 ratings) — better
Positive reviews—66.7% of reviews
Number of ratings—2 — better
Update frequencyDaily — betterEvery 5 days
AdsNoNo
In-app purchasesYesYes
Monetization—Freemium
DevicesiPhoneiPhone
Requires iOS18.517.0 — better
Further details — not scored
Size5 MB33 MB
Age rating4+4+
DeveloperFrearBros Labs USA Inc.Trader Prosperity LLC

In-app purchases

1 purchases

RacketLog

Subscriptions1
  • RacketLog Premium$14.991 Year
3 purchases

String Tension AI

Subscriptions2
  • Monthly PRO$4.991 Month
  • Annual PRO$29.991 Year
One-time1
  • Lifetime PRO$69.99

Questions

Is RacketLog free?
RacketLog is free to download, with in-app purchases available.
Is String Tension AI free?
String Tension AI is free to download, with in-app purchases available.
Do RacketLog or String Tension AI have ads?
Neither RacketLog nor String Tension AI shows ads.
Which is updated more often, RacketLog or String Tension AI?
RacketLog ships an update daily, and String Tension AI every 5 days. Most recently, RacketLog was updated on August 20, 2026 and String Tension AI on September 23, 2026.

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