Comparison

10K Trainer by C25K® vs RUN interval

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

Head to head
About

10K Trainer by C25K®

This app guides beginners from sedentary to running a 10K in 14 weeks with a structured walk/run program. It features an audio coach, progress tracking, and community support. Ideal for those new to running or graduating from a 5K program.

Highlights
  • 14-week walk/run training plan
  • Audio coach guidance
  • Progress tracking
  • Community forums
  • Integration with Health app
  • Music integration
Features
Read full description

■ The Official 10K Trainer app with millions of success stories! ■ Official partners and the ONLY C25K (Couch to 5K) app featured on FITBIT and SAMSUNG smart watches! ■ Featured on The New York Times, Los Angeles Times, The Washington Post, The Guardian, The Huffington Post, Men's Fitness, Forbes, Mashable, Glamour Magazine, Popsugar Fitness, CBS News, NBC News, Macworld, Cosmopolitan, Lifehacker, WebMD and many more! "Daily programs that alternate between short bursts of walking and running until you're ready to go the distance." - Forbes "One of the highest-rated health and fitness apps... A modest, realistic workout schedule." - Men's Fitness ≈ Real-Life Inspirational Transformations ≈ ◎ Over 175,000 Likes and 1500 Success Photos at facebook.com/c25kfree ◎ Our community inspires one another (and inspires us!) everyday. Hear some of their amazing stories. "In this last year I have lost 97 lbs, gotten off insulin and 9 other medications, completed the C25K running app and started the 10k app. Life is a blessing." - Diana “I went from a size 16 to a size 7. I tell anyone I can about the app. because it was nothing short of a life changer.” - Amber 10K Trainer is the easiest program to get beginners from couch potatoes to 10K distance runners in just 14 weeks. By the same experts who created the #1 C25K® (Couch to 5K) training app! Don’t worry, if you are already a 5K graduate, you can skip ahead and pick up where C25K® app leaves off! This proven 14 week plan will allow users to slowly build strength and stamina by alternating between walking and running. The blend of walking and running together reduces the overall impact and risk of injury, keeps your body guessing, and prepares you to go the distance. By the end of the program, you will be stronger and healthier than you have ever been. You'll be a 10K runner! Turn on our award winning music and just press start! Our audio coach will guide you through your run! It's that easy! ≈ Less is More ≈ ◎ First week free! Easy to learn. Just press start! ◎ Ideal for beginners. ◎ 14 weeks total. ≈ Features ≈ ◉ Easiest 10k program at only 3 times/week ◉ Convenient audio coach and alerts ◉ Map your run at the end of your workout! ◉ Light and dark modes ◉ Integrates with the Health app ◉ Free iPad integration for indoor treadmills ◉ Integrated with Facebook, Twitter, and Instagram ◉ Access to our forums with thousands of veterans and newcomers starting the app. Join the community and meet other runners! ≈ NEW Zen Unlimited Pass - Try it for free! ≈ ◉ Award winning music curated from top DJ's! ◉ Scientifically proven to increase motivation by 35% ◉ Unlimited access to all pro features across ALL Zen Labs Fitness apps ◉ Unlock calories, distance, Apple watch integration, and more ◉ One subscription unlocks all our apps! Questions/comments? Please email us at contactus@zenlabsfitness.com, or visit us at www.zenlabsfitness.com. ≈ Connect ≈ Facebook: @C25Kfree Twitter: @C25Kfree Instagram: @officialc25k Hashtag: #C25K Zen Labs is a proud supporter of the National Breast Cancer Coalition. breastcancerdeadline2020.org Subscription pricing and terms: The subscription will automatically renew unless turned off in your iTunes Account Settings at least 24 hours before current period ends. You can go to your iTunes Account settings to manage your subscription and turn off auto-renew. Your iTunes Account will be charged when the purchase is confirmed. If you subscribe before your free trial ends, the rest of your free trial period will be forfeited as soon as your purchase is confirmed. Privacy Policy & Terms of Use: https://www.zenlabsfitness.com/privacy-policy/ Legal Disclaimer This app and any information given by it or by Zen Labs LLC are for educational purposes only. You should always consult your healthcare provider before beginning any fitness program. C25K® is a registered trademark of Zen Labs LLC

About

RUN interval

This app simplifies interval and Fartlek running by allowing you to set custom targets for time or distance during hard, easy, and rest efforts. It offers detailed post-run summaries, audio and visual feedback, and an Apple Watch app for enhanced training.

Highlights
  • Customizable interval sessions
  • Time and distance targets
  • Distance Goal option
  • Audio and visual feedback
  • Detailed run summaries
  • Apple Watch app
  • Strava sharing
Features
Read full description

Easily set up and record your Interval and Fartlek running sessions. With the flexibility of using time and/or distance as interval targets for your "Hard", "Easy" and "Rest" efforts. The simple but highly configurable interface on your phone and watch will have you running sooner. Now with a Distance Goal option for your session. Along with great audio and visual feedback, detailed post-run summary, share your runs to Strava, and a full-featured Apple Watch app. You can also record your regular runs with voice-over calling out distance and pace feedback. Key Features: • Easily create flexible custom interval sessions. • Utilize three effort targets "Hard", "Easy" and "Rest" in each set, targeting time or distance (meters or miles). • You can "Skip" any of the three efforts to create flexible sets, like building a progressive intervals session. • NEW: Set a Distance Goal for your session, that repeats the sets from the start until the distance has been reached. • Set a Warm-Up and Warm-Down timer or distance around your session. • Clear and easily glanceable visuals and audio prompts, including vibrations. • Voice-over prompts to save you from looking at the screen, great for iPhone or headphone users. • Voice-over prompts include the upcoming intervals effort and time/distance amount, and your last intervals average pace and heart rate. • Full-featured Apple Watch App! • Heart Rate Zones! (see description below) • Indoor Mode, no GPS, for treadmill running. • Sound Mode, for normal, discrete or silent audio prompts on your watch. • Vibration feedback on both the phone and watch. • Detailed run summary, showing pace for hard and easy efforts. • The run summary also includes interval breakdown, distance breakdown and heart rate details. • Play music or podcasts while running and still hear the audio prompts. • Sharing. Share a summary photo with your friends. • Private data. We don’t send any of your data to a server or share it with anyone. Session Types: • Normal Run – Record a normal run, long or short. • Record Intervals – If you run with a group or do an undefined session, then use the Record Interval option. It allows you to manually change between "Hard" and "Easy" reps, allowing you to record your session. • Custom Intervals – Our fully flexible intervals that allow you to use time and/or distance for the efforts. Add multiple intervals sets together to create the session you want. Sharing: From the summary screen, you can share your runs with friends or across social media. If you want to share directly with friends or across other social media, you can share a summary image with the details of your run. Heart Rate Zones: (Apple Watch Only) Zones are displayed as grouped percentages of your maximum heart rate. Giving you an indication of your current work rate based on your current heart rate. Just enter your maximum workout heart rate into our Settings screen and they will display on your Watch the next time you run. Zone 1: Very Light Effort 50-60% (Gray) Zone 2: Light Effort 60-70% (Blue) Zone 3: Moderate Effort 70-80% (Green) Zone 4: Hard Effort 80-90% (Yellow) Zone 5: Maximum Effort 90-100% (Red) Privacy: We don’t want to know where you have run, that's for you to worry about. We don’t send any of your data to a server or share it with anyone you don't want too. We keep your running records safe in Apple Health so you have control. Apple Heath gives you the control over who accesses your data. We only write and read the data we record from your running. Feedback: And because we don't send any data to a server, we need you to send us feedback and suggestions. Hit the Support link below or visit our website to contact us.

Screenshots

10K Trainer by C25K®4 screens
RUN interval4 screens

Verdict

The call

The clearest difference is ads: RUN interval at none against 10K Trainer by C25K®'s shown. 10K Trainer by C25K®'s advantage is ratings volume (22K vs 1K). On price, rating, review sentiment and update cadence 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. 10K Trainer by C25K® sells 6 in-app purchases, starting at $4.99 per month and RUN interval sells 2 one-off in-app purchases. Whichever you choose, the download price is not the number that matters.

ReceptionRating · Positive reviews · Number of ratings

On the App Store both sit at effectively the same score — 4.8 for 10K Trainer by C25K® against 4.7 for RUN interval. That said, the two scores are not equally well evidenced: 10K Trainer by C25K® has 22K ratings behind it against 1K, so its average is the more settled of the two. Written reviews are what separate them: 76% of 10K Trainer by C25K®'s written reviews are positive against 77% of RUN interval's.

UpkeepUpdate frequency

10K Trainer by C25K® ships an update every 6 weeks, RUN interval every 3 months. The most recent releases landed on October 20, 2026 and October 21, 2026 respectively.

Scorecard2 real differences · 8 level
10K Trainer by C25K® versus RUN interval: the parameters behind the verdict, then further details
Parameter10K Trainer by C25K®RUN interval
PriceFreeFree
Rating4.8 (22K ratings) — better4.7 (1K ratings)
Positive reviews76.2% of reviews77.5% of reviews — better
Number of ratings22K — better1K
Update frequencyEvery 6 weeks — betterEvery 3 months
AdsYesNo — better
In-app purchasesYesYes
MonetizationFree with in-app purchasesFree with in-app purchases
DevicesiPhone, iPad, iPod, Apple Watch — betteriPhone, iPod, Apple Watch
Requires iOS14.0 — better15.6
Further details — not scored
Size321 MB34 MB
Age rating4+4+
DeveloperZen LabsCAN YOU HEAR ME SOFTWARE

Customer experience

10K Trainer by C25K®

All ratings21,551 ratings
Positive95.8%
Neutral2.0%
Negative2.2%
Written reviews420 reviews
Positive76.2%
Neutral6.2%
Negative17.6%

RUN interval

All ratings1,003 ratings
Positive94.3%
Neutral1.6%
Negative4.1%
Written reviews191 reviews
Positive77.5%
Neutral5.2%
Negative17.3%

Bugs and requests

10K Trainer by C25K®

Reported bugs

2 issues
  • Timers not syncing accurately with other devices
  • Workout data sometimes not recorded properly

Requested features

3 requests
  • Apple Watch integration for standalone use
  • More advanced training options beyond just 10K
  • Ability to customize audio prompts and volume

RUN interval

Not enough reviews yet to summarise bugs or requests.

In-app purchases

6 purchases

10K Trainer by C25K®

Subscriptions4
  • Zen Unlimited Pass Monthly1 Month trial$4.991 Month
  • Unlock Your Potential7 Days trial$29.993 Months
  • Unlock Your Potential1 Month trial$29.993 Months
Show 1 more
  • Zen Unlimited Pass Annual7 Days trial$74.991 Year
One-time2
  • Remove Ads$1.99
  • Go To Pro$6.99
2 purchases

RUN interval

One-time2
  • The full RUN interval$1.99
  • The full RUN interval$3.99

Questions

Is 10K Trainer by C25K® free?
10K Trainer by C25K® is free to download, with in-app purchases available.
Is RUN interval free?
RUN interval is free to download, with in-app purchases available.
Which has better reviews, 10K Trainer by C25K® or RUN interval?
10K Trainer by C25K® is rated higher. 10K Trainer by C25K® averages 4.8 out of 5 from 22K ratings, while RUN interval averages 4.7 from 1K ratings.
Do 10K Trainer by C25K® or RUN interval have ads?
10K Trainer by C25K® shows ads; RUN interval does not.
Which is updated more often, 10K Trainer by C25K® or RUN interval?
10K Trainer by C25K® ships an update every 6 weeks, and RUN interval every 3 months. Most recently, 10K Trainer by C25K® was updated on October 20, 2026 and RUN interval on October 21, 2026.

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