Comparison

Seconds Pro Interval Timer vs B3

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

Head to head
About

Seconds Pro Interval Timer

This interval timer app is designed for high-intensity interval training (HIIT), Tabata, and circuit training workouts. It features a large, color-coded display, customizable interval names, and background operation. It also integrates with Apple Health to track your fitness data.

Highlights
  • Full screen colored display
  • Templates for HIIT, Tabata, Circuit Training
  • Speaks interval names and provides warnings
  • Assign music per interval
  • Runs in background
  • Share interval timers
  • Apple Health integration
Features
Read full description

Seconds Pro is an interval timer for HIIT, Tabata, EMOM, circuits and any workout built from timed intervals. It calls each interval out loud, keeps running with the screen off, and runs on iPhone, iPad and Apple Watch. Apple has featured it, and Joe Wicks, The Body Coach, has said it is the fitness app he uses more than any other. BUILD ANY WORKOUT - Start from a HIIT, Tabata or circuit template, or build a timer from scratch with sets, rounds and intervals of different lengths. - Chain timers into one compound timer, so a warm-up flows into the main set and then a cool-down. - Color-code every interval so you know what is coming before the beep. - Share a timer with a friend in one tap. HEAR IT, DON'T WATCH IT - Voice cues call out each interval by name and warn you before the next one starts. - Beeps and bells are there too if you would rather not be talked at. - Play your own music, per timer or per interval. Cues duck the music and it comes back up when they are done. - The timer keeps going in the background while you use other apps or the screen sleeps. ON THE GYM FLOOR - A full-screen, color-coded display you can read from across the room, in portrait or landscape. On iPad it uses the whole screen. - A lock button stops a stray tap from pausing your set. APPLE WATCH - Seconds Pro runs on the watch by itself, so the phone can stay in the locker. Timers you build on the phone sync to the wrist, and Quick Intervals builds a basic circuit on the watch itself. MORE TIMERS - A stopwatch that marks your best and worst laps. - A countdown timer with five preset durations (three on Apple Watch). APPLE HEALTH - Save workouts and mindful sessions to Health. With a heart rate monitor connected, Seconds Pro reads your body measurements and year of birth from Health to estimate calories burned. PAID ONCE, NOTHING TO UNLOCK - Seconds Pro is paid for up front. Every feature is included and every timer you make can be run as many times as you like. SECONDS AND SECONDS PRO - Seconds is the free version of this app. It has the same features, but each timer locks after one run until a single in-app purchase unlocks it. The two are separate products and a purchase in one does not carry over to the other. If you bought Seconds Pro, download Seconds Pro. If you bought the unlock in Seconds, download Seconds and use Restore Purchases.

About

B3

This app offers personalized coaching for body, habits, and lifestyle transformations. Connect with certified coaches for tailored training, nutrition, and progress tracking to build strength and confidence.

Highlights
  • Customized coaching experience
  • Personalized training and nutrition
  • Progress tracking
  • Habit and lifestyle guidance
  • Direct coach communication
  • Health app integration
Features
Read full description

The Bodies by Bombshell (B3) app delivers a fully customized coaching experience designed to support your entire transformation - body, habits, mindset, and lifestyle. Connect directly with Certified Bombshell Coaches for personalized training, nutrition guidance, progress tracking, and daily structure that fits your goals. Every program is tailored. Every workout is intentional. Every tool is created to help you build strength, confidence, and lasting change from the inside out. B3 helps you stay consistent, understand your training, upgrade your habits, and step into a healthier, more powerful version of yourself. It’s your all-in-one path to a complete Bombshell glow-up. Sync with the Health app to update your metrics instantly. Strong. Confident. Bombshell. Medical Information: The meal plan and nutritional guidance provided in this app are based on resources and information available from the following websites: 1. National Heart, Lung, and Blood Institute (NHLBI) Offers evidence-based information on healthy eating, calorie management, and dietary approaches to support heart health and overall wellness. https://www.nhlbi.nih.gov 2. Healthy Eating by NHLBI Offers practical dietary guidance, heart-healthy recipes, and tools to support individuals in adopting healthier eating patterns. https://healthyeating.nhlbi.nih.gov/ 3. USDA FoodData Central A comprehensive database providing detailed nutritional information for a wide range of foods, supporting informed dietary choices. https://fdc.nal.usda.gov/

Screenshots

Seconds Pro Interval Timer4 screens
B34 screens

Verdict

The call

The clearest difference is price: B3 at Free against Seconds Pro Interval Timer's $7.99. B3 also leads on rating (5.0 vs 4.8) and iOS requirement (13.0 vs 18.0). Seconds Pro Interval Timer's advantage is ratings volume (12K vs 5) and chart position (#10 vs unranked). On update cadence, 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

B3 is free to download; Seconds Pro Interval Timer costs $7.99 up front. Neither carries in-app purchases, so what you see is what you pay.

ReceptionRating · Positive reviews · Number of ratings

B3 holds the better App Store score, 5.0 against 4.8. That said, the two scores are not equally well evidenced: Seconds Pro Interval Timer has 12K ratings behind it against 5, so its average is the more settled of the two.

UpkeepUpdate frequency

Seconds Pro Interval Timer ships an update fortnightly, B3 monthly. The most recent releases landed on October 14, 2026 and October 6, 2026 respectively.

Scorecard6 real differences · 5 level
Seconds Pro Interval Timer versus B3: the parameters behind the verdict, then further details
ParameterSeconds Pro Interval TimerB3
Price$7.99Free — better
Rating4.8 (12K ratings)5.0 (5 ratings) — better
Positive reviews79.7% of reviews—
Number of ratings12K — better5
Update frequencyFortnightly — betterMonthly
AdsNoNo
In-app purchasesNoNo
MonetizationPaidFree with in-app purchases — better
Best chart rank#10 — better—
DevicesiPhone, iPad, Apple WatchiPhone, iPad, iPod
Requires iOS18.013.0 — better
Further details — not scored
Size94 MB419 MB
Age rating4+4+
DeveloperRunloop LtdBombshell Fitness

Customer experience

Seconds Pro Interval Timer

All ratings12,104 ratings
Positive94.7%
Neutral1.9%
Negative3.4%
Written reviews1,520 reviews
Positive79.7%
Neutral6.0%
Negative14.3%

B3

All ratings5 ratings
Positive100.0%
Neutral0.0%
Negative0.0%

Bugs and requests

Seconds Pro Interval Timer

Reported bugs

4 issues
  • Intervals randomly pausing or skipping
  • Music volume issues when launching the app
  • Inconsistent audio cues and countdown
  • Sync issues between devices

Requested features

6 requests
  • Ability to lock Apple Watch screen
  • Option to see more than just the next exercise
  • Fractional time settings (e.g. 7.74 seconds)
  • More voice/audio customization options
  • Improved sync between iPhone and iPad
Show 1 more
  • Calendar integration to track workouts

B3

Not enough reviews yet to summarise bugs or requests.

In-app purchases

None

Seconds Pro Interval Timer

No in-app purchases

None

B3

No in-app purchases

Questions

Is Seconds Pro Interval Timer free?
Seconds Pro Interval Timer costs $7.99, with no in-app purchases.
Is B3 free?
B3 is free to download, with no in-app purchases.
Which has better reviews, Seconds Pro Interval Timer or B3?
B3 is rated higher. Seconds Pro Interval Timer averages 4.8 out of 5 from 12K ratings, while B3 averages 5.0 from 5 ratings.
Do Seconds Pro Interval Timer or B3 have ads?
Neither Seconds Pro Interval Timer nor B3 shows ads.
Which is updated more often, Seconds Pro Interval Timer or B3?
Seconds Pro Interval Timer ships an update fortnightly, and B3 monthly. Most recently, Seconds Pro Interval Timer was updated on October 14, 2026 and B3 on October 6, 2026.

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