Outdoor Training Intelligence
Time
It Right
Zeph scores every hour for your sport—run at 6 AM, not noon. One app, one answer.
Join 500+ athletes on the waitlist · iOS coming soon
Stop checking three apps. Get one score.
Zeph analyzes real-time weather against your sport—then tells you exactly when to go. A 9 means lace up. A 4 means wait.
One Number, Zero Guesswork
Open Zeph, see your score. 9 means ideal conditions. 4 means wait. That's it—no data to interpret, no math to do.
Tuned to Your Sport
75°F humidity is brutal for running, fine for cycling. Zeph adjusts every threshold to match how your body responds.
Conditions Shift. So Does Your Score.
Front moving in? Your 6 AM window just became a 4 PM window. Zeph recalculates automatically.
Find Your Perfect Window
Hour-by-hour scores show you exactly when conditions peak. Tomorrow at 6:15 AM scores a 9. By noon it drops to 4. Now you know.
Built for Your Sport
A cyclist's perfect day isn't a runner's. Zeph adjusts thresholds for wind resistance, heat tolerance, and UV exposure based on your activity.
Never Miss Your Window
Morning briefing at 6 AM tells you today's best window. Or get a heads-up 30 minutes before conditions peak. Your call.
Why Zeph
Stop checking multiple apps.
Get one answer.
Without Zeph
- ✕ Check Weather.app, then Strava, then UV index, then convert "feels like" to running impact
- ✕ Guess if 68°F with 80% humidity is better than 72°F with wind gusts
- ✕ Scroll through hourly forecasts trying to mentally calculate "best window"
- ✕ End up running at lunch because you ran out of time analyzing data
With Zeph
- ✓ Open one app. See "Run at 6:30 AM - Score: 9"
- ✓ Algorithm weighs all 7 factors based on physiological research, not guesswork
- ✓ Get notified when your window opens—no manual checking
- ✓ Train at peak conditions, then get on with your day
How It Works
Pick Your Workout
75°F with 80% humidity is brutal for a tempo run but fine on the bike. Select your sport and Zeph adjusts every threshold to match how your body actually responds.
Get Your Window
Open Zeph and see one score and one optimal window. Every weather factor weighed by physiological impact. The guesswork is gone.
Just Go
Morning briefing or pre-window alert—you choose. When conditions line up, you'll know. Just a notification, a score, and the confidence to go.
Simple, Transparent Pricing
Start with a 7-day free trial.
Cancel anytime. No hidden fees.
Save 30% with Annual
Monthly
Never miss your ideal workout window
- 7-day free trial
- Check conditions anytime
- Run, cycle, walk, HIIT recommendations
- 7-day weather outlook
- Smart training window alerts
Annual
~ $4.17/month
Never miss your ideal workout window
- 7-day free trial
- Check conditions anytime
- Run, cycle, walk, HIIT recommendations
- 7-day weather outlook
- Smart training window alerts
Cancel anytime in 2 taps. No questions asked.
FAQs
Got questions?
We've got accurate answers.
How is this different from a regular weather app?
Most weather apps just show raw data. Zeph interprets that data specifically for athletic performance. We analyze every weather factor combined with your specific activity type (Run, Cycle, HIIT) to give you a single 0–10 score and the exact best time to train.
Doesn't Strava already show weather data?
Strava shows weather after your workout (for logging and activity context), not predictive recommendations. Zeph tells you when to go before you lace up, based on your specific activity's weather sensitivity. Think of it as the difference between a post-workout report card and a pre-workout coach giving you the optimal training time.
What notifications can I receive from Zeph?
Zeph offers two types of smart notifications to help you never miss your ideal workout window:
- Morning Briefing - A daily weather summary showing your best workout window for the day, delivered at your chosen time (great for planning your workout schedule)
- Window Alerts - A reminder notification sent before your optimal workout window starts. You can configure this for 15, 30, or 60 minutes before the ideal time, giving you enough notice to prepare
Both notification types are completely optional and can be customized or disabled based on your preferences.
Know when.
TRAIN SMART.
STOP GUESSING. START TRAINING.
Tomorrow's Best Window Is Already Calculated
Join 500+ outdoor athletes who wake up knowing exactly when to train. Get your score before you get out of bed.
No spam, ever. iOS launch coming soon.