Comparison

RUN interval vs Tars

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

Head to head
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.

About

Tars

Features
Read full description

Whether it's a relationship that keeps hitting the same wall, or a decision you can't stop second-guessing — you're not stuck because you don't care. You're stuck because you don't have the right support in the room. That's what Tars is for. Tars is an AI coach and mediator that listens to real conversations — between partners, or with yourself — and helps you move forward. Not with scripts or generic advice, but with insight drawn from what you actually said. Here's how it works: 1. Start a session Open the app and speak freely. For couples, place your phone between you — Tars automatically tells your voices apart from a single shared mic. 2. Talk. Just talk. Tars listens in real time. It knows when to stay quiet and when to speak. When it does, it reframes, translates, and helps you hear each other differently. 3. Walk away with clarity Every meaningful session produces a full report — themes, emotional patterns, key moments, and next steps. Over time, Tars builds a personalised insight profile so you can see your own growth. What changes when you have Tars: → Conversations stop going in circles → You feel heard — and so does the person across from you → Decisions stop feeling paralysing → You have a record of what actually happened and what to do next → Private by Design — Sign in with a passkey, Google, or Apple. No email required. Your sessions are yours. Tars is an AI relationship coach and does not provide medical, psychological, or therapeutic diagnosis or treatment. It is not a substitute for professional therapy, counseling, or medical care. Always consult a licensed therapist, counselor, or physician before making decisions about your mental health or relationship, and seek immediate help from local emergency services or a crisis hotline if you are in crisis.

Screenshots

RUN interval4 screens
Tars4 screens

Verdict

The call

The clearest difference is update cadence: Tars at weekly against RUN interval's every 3 months. Tars also leads on iOS requirement (13.0 vs 15.6). 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. RUN interval sells 2 one-off in-app purchases and Tars sells 8 in-app purchases, starting at $4.99 per month. Whichever you choose, the download price is not the number that matters.

UpkeepUpdate frequency

RUN interval ships an update every 3 months, Tars weekly. The most recent releases landed on October 18, 2026 and September 30, 2026 respectively.

Scorecard2 real differences · 8 level
RUN interval versus Tars: the parameters behind the verdict, then further details
ParameterRUN intervalTars
PriceFreeFree
Rating4.7 (1K ratings) — better—
Positive reviews77.5% of reviews—
Number of ratings1K — better—
Update frequencyEvery 3 monthsWeekly — better
AdsNoNo
In-app purchasesYesYes
MonetizationFree with in-app purchases—
DevicesiPhone, iPod, Apple WatchiPhone, iPad, iPod
Requires iOS15.613.0 — better
Further details — not scored
Size34 MB29 MB
Age rating4+4+
DeveloperCAN YOU HEAR ME SOFTWARENerdstorm Pty Ltd

In-app purchases

2 purchases

RUN interval

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

Tars

Subscriptions6
  • Solo Growth Monthly$4.991 Month
  • Couples Growth Plan Monthly$9.991 Month
  • Growth Plan (Monthly)$14.991 Month
Show 3 more
  • Solo Growth Plan Yearly$39.991 Year
  • Growth Plan (Yearly)$79.991 Year
  • Couples Growth Plan Yearly$79.991 Year
One-time2
  • 1x Session Report$4.99
  • 5x Session Reports$14.99

Questions

Is RUN interval free?
RUN interval is free to download, with in-app purchases available.
Is Tars free?
Tars is free to download, with in-app purchases available.
Do RUN interval or Tars have ads?
Neither RUN interval nor Tars shows ads.
Which is updated more often, RUN interval or Tars?
RUN interval ships an update every 3 months, and Tars weekly. Most recently, RUN interval was updated on October 18, 2026 and Tars on September 30, 2026.

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