Comparison

Keep your reflexes vs Sub250

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

Head to head
About

Keep your reflexes

Features
Read full description

FlashFive is a fun training game that helps you boost your focus and improve your reaction speed! Five circles appear on the screen, and your goal is to tap the one that lights up within the time limit. The time gets shorter little by little, but don’t rush—take your time and enjoy the challenge. Your score is based on how many circles you tap correctly. Play at your own pace and steadily train your concentration while having fun. Try playing a little every day to refresh your mind and body!

About

Sub250

Measure your reflexes with precision using multiple modes. This app calibrates your device's latency for accurate results and focuses on median scores over luck. It's designed for competitive gamers who need to understand their true reaction speed.

Highlights
  • Multiple reaction-time modes
  • Device latency calibration
  • Median score calculation
  • Anti-anticipation features
  • No accounts or servers
  • Local-only data storage
Features
Read full description

Five reaction-time modes with native iOS timing. Your device's latency floor shows next to every score in ms. What's reflex, what's hardware. Free. Sub250 measures your reflexes the way they should be measured. The headline number is the median of your last ten attempts, not your luckiest tap, with millisecond-level precision and your device's calibrated latency floor shown alongside every score. FIVE REACTION-TIME MODES • Simple RT: wait for green, tap as fast as you can. • F1 Lights Out: five red lights, then go, exactly like the grid. • Go / No-Go: tap green, hold red. The clock catches you if you flinch. • Choice RT: four zones, react to whichever lights up. • Target Hunt: tap pop-up targets in random spots before they fade. Thirty seconds. WHY SUB250 IS DIFFERENT Latency-honest. Every device adds touch-to-display latency. Sub250 calibrates yours in about three seconds at startup and shows the floor in milliseconds next to every score. We think every reaction-test app should. Median-of-10. The score reflects skill, not variance. Best-of-N is available as a secondary number, never the headline. Anti-anticipation. Randomized stimulus intervals on every interval-based mode. Jumpstarts cost a re-arm. The clock is honest. 100% free. No accounts. No servers. No subscriptions. No ads. No in-app purchases. Ever. Local-only. Your sessions never leave your device. There is no leaderboard to game, no profile to fill out, no email to give up. BUILT FOR COMPETITIVE GAMERS If you play Counter-Strike, Valorant, Apex, racing sims, or anything else where the difference between 200 and 230 ms matters, Sub250 was built for you. The score is the score. Open Sub250, run the calibration, and see what your real reflex looks like.

Screenshots

Keep your reflexes2 screens
Sub2504 screens

Verdict

The call

The clearest difference is ads: Sub250 at none against Keep your reflexes's shown. Keep your reflexes's advantage is update cadence (every 2 days vs weekly) and device support (3 vs 1). On price, in-app purchases and iOS requirement 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. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

Keep your reflexes ships an update every 2 days, Sub250 weekly. The most recent releases landed on September 26, 2026 and October 7, 2026 respectively.

Scorecard3 real differences · 6 level
Keep your reflexes versus Sub250: the parameters behind the verdict, then further details
ParameterKeep your reflexesSub250
PriceFreeFree
Rating—5.0 (2 ratings) — better
Number of ratings—2 — better
Update frequencyEvery 2 days — betterWeekly
AdsYesNo — better
In-app purchasesNoNo
Monetization—Free
DevicesiPhone, iPad, iPod — betteriPhone
Requires iOS15.6 — better16.4
Further details — not scored
Size5 MB49 MB
Age rating4+4+
DeveloperMasaharu TsukamotoPierre Caporossi

In-app purchases

None

Keep your reflexes

No in-app purchases

None

Sub250

No in-app purchases

Questions

Is Keep your reflexes free?
Keep your reflexes is free to download, with no in-app purchases.
Is Sub250 free?
Sub250 is free to download, with no in-app purchases.
Do Keep your reflexes or Sub250 have ads?
Keep your reflexes shows ads; Sub250 does not.
Which is updated more often, Keep your reflexes or Sub250?
Keep your reflexes ships an update every 2 days, and Sub250 weekly. Most recently, Keep your reflexes was updated on September 26, 2026 and Sub250 on October 7, 2026.

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