I'm Yoi. Your brain's avatar.
How long have you been awake?
If you can't answer right away, you're probably already slipping. A sleep-deprived brain performs like a drunk one — after 17 hours awake, cognitive tests drop to tipsy levels; at 24 hours, reaction time matches someone well over the limit. That's not a scare tactic — it's a measured finding from occupational medicine research. The nasty part? You're the only one who can't tell. Studies have shown that "I'm fine without sleep" is the least reliable self-report there is.
So I'll break down in your place.
The longer you stay up, the more I turn yellow, then red, then cracked and lifeless. That progression is your "Debuff Score" (0–150). Think of it as your brain's status screen in a game — a real-time number and gauge showing how wrecked you really are.
WHAT YOU CAN DO
- Real-time Debuff Score with a BAC (blood-alcohol) equivalent
- HP, Focus, and Judgment gauges plus status-ailment labels
- Second-by-second countdown to tonight's bedtime limit
- Aggressive nudges at night; just the facts in the morning (no lectures when it's too late to change anything)
- Log sleep with a single "Sleep" / "Woke up" tap — and backfill missed days with "Around here?"
- Optional auto-import from Apple Health (HealthKit)
- Weekly wake-up schedule with per-day overrides for shift workers
- Auto-shield games and social media at bedtime (Screen Time) with optional Strict Shield
- Bedtime-rhythm scatter chart and 30-day trend graph
- 5-axis Sleep Score (Duration / Continuity / Regularity / Timing / Architecture)
- No penalty for skipped days — streaks count "days logged this month," not consecutive runs
FREE VS PRO
Everything that gets you to bed is free. Debuff Score, notifications, schedule, shield (including Strict Shield), sleep log, last 7 days of data, and overall Sleep Score — no paywall. Pro (one-time purchase) adds 5-axis score breakdown, stage timeline, biometrics (heart rate / HRV / respiratory rate), unlimited daily detail history, month-over-month comparison, trend analysis, custom notification wording, and shift patterns. Nice-to-haves, not need-to-haves.
ONE HONEST NOTE
I'm not a medical device and I can't diagnose anything. The Debuff Score is a research-based estimate, not a clinical reading. Also, I'm bad at waking you up — use the built-in alarm for mornings.
My job ends when you're in bed. Let's start tonight.
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