Seconds Interval Timer vs ImersU
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Seconds Interval Timer
This app provides a versatile interval timer for various workout types like Tabata, HIIT, and circuit training. It features a clear, full-screen display, customizable alerts, and background operation. Users can also utilize a stopwatch and countdown timer, with integration for Apple Health.
- Full-screen colored display
- Templates for HIIT, Tabata, Circuit Training
- Voice and audio alerts
- Music assignment per interval
- Background operation
- Apple Health integration
- Stopwatch and countdown timer
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Seconds 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 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 reads your body measurements and year of birth from Health to estimate calories burned. FREE TO TRY, ONE PAYMENT TO UNLOCK - Everything is available from the first launch. Build any timer and run it. - Each timer locks after you run it once. A single in-app purchase removes the lock on every timer you make. SECONDS AND SECONDS PRO - Seconds Pro is the same app, paid once up front, with nothing to unlock. 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.
ImersU
Experience indoor rowing like never before with virtual, real-world courses. Train or race against AI, customize your environment, and connect with your rowing machine for an immersive fitness journey.
- Virtual real-world rowing courses
- Customizable time of day and weather
- AI boat racing
- Connects with rowing machines via Bluetooth FTMS
- Flow Row mode for non-connected ergometers
- Multi-screen display support
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ImersU ROW helps make indoor rowing more enjoyable and rewarding by bringing the outdoors indoors. Row virtually on stunning, real-world courses, select time of day, weather, and viewing perspective. Train or Race against AI boats, challenge yourself, or take yourself out for a paddle. Pair with your ergo for a connected row or simply choose your speed and get into the flow so you can enjoy mersU on every rowing ergo. Rowing is the most efficient form of training compared to running and cycling, with over 86% of muscle groups being used. Many people have shied away from indoor rowing as it was considered boring. But no more. Combine the most efficient form of indoor training with stunning content, game play, and a growing community, and rowing is becoming the go-to choice for indoor training. Join the growing number of people making indoor rowing a central part of their fitness regime. With imersU, you can row in multiple locations, including Tokyo, Paris, Henley, and The Tideway. Turn your home rowing machine or gym session into a journey shared by elite athletes. imersU uses standard Bluetooth FTMS protocol so you can connect to compatible devices; these include Concept 2 PM5 and the WaterRower S4. There is also a Companion App, should you wish to connect on Windows and race against up to 7 other competitors when in the same room. The imersU content has been created to be displayed on all the latest phones and tablets as well as on high-powered MACS and PCs, so you can choose how you experience imersU ROW. At its most immersive, imersU can be displayed on super-sized screens on 3 walls to give you that on-water experience of having other rowers ‘on your shoulder. The app comes with NDI screen settings for connection to multiple monitors to make this possible. For the first time, you can join a rowing community whilst creating a rowing environment that suits your needs. An equivalent of a Maybach to an A-Class. Some users may not have the latest ergo that can connect to the imersU app, but they still want to be able to row on iconic courses. imersU has FLOW ROW, a feature that lets the user set a split time and then row in FLOW with the course environment as the ergo speed is matched to the selected split time. imersU will turn every training session into an experience that will keep you motivated and engaged to help you become fitter and stronger. WHY CHOOSE imersU ROW: • Stunning graphics created in Unreal Engine 5, an industry pioneer in creating virtual environments, are designed to inspire you as if you were in the great outdoors, but where you control the weather. • The ability to connect to multiple screens to create an indoor rowing environment that can be fully immersive and extensive, as you choose, or simply enjoyed on a tablet. • Use the benefits of virtual environments to add in AI boats to race against and help you focus on your goals. • Choose your time of day, weather, and viewing perspective, and track how your performance can be affected by your environment. • Enjoy imersU on every single rowing ergo with the FLOW ROW feature as well as enjoy connected rowing on leading Bluetooth-enabled ergos. SUPPORTING THE COMMUNITY imersU believes in the benefits that rowing can bring to the community. As a result, imersU has special rates and arrangements with all those under 15, schools and rowing clubs to enable as many people as possible to experience rowing in the places rowed by the elite rowers. For everyone else, imersU can be enjoyed in an unlimited way each month for £14.99, with some prices affected by currency. Your involvement in imersU will help those new to rowing enjoy the benefits indoor rowing brings. Please see Terms of Use at https://row.imersu.com/register
Screenshots
Verdict
The clearest difference is rating: Seconds Interval Timer at 4.7 against ImersU's 3.0. Seconds Interval Timer also leads on ratings volume (24K vs 2) and review sentiment (75% vs 60%). ImersU's advantage is in-app purchases (none vs 1) and iOS requirement (15.0 vs 18.0). On price, update cadence, ads 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
Both are free to download. Seconds Interval Timer sells 1 one-off in-app purchase. ImersU asks for nothing beyond the download.
Seconds Interval Timer holds the better App Store score, 4.7 against 3.0. That said, the two scores are not equally well evidenced: Seconds Interval Timer has 24K ratings behind it against 2, so its average is the more settled of the two. Written reviews point the same way: 75% of Seconds Interval Timer's written reviews are positive against 60% of ImersU's.
Seconds Interval Timer ships an update monthly, ImersU every 2 weeks. The most recent releases landed on September 24, 2026 and September 10, 2026 respectively.
| Parameter | Seconds Interval Timer | ImersU |
|---|---|---|
| Price | Free | Free |
| Rating | 4.7 (24K ratings) — better | 3.0 (2 ratings) |
| Positive reviews | 75.0% of reviews — better | 60.0% of reviews |
| Number of ratings | 24K — better | 2 |
| Update frequency | Monthly | Every 2 weeks — better |
| Ads | No | No |
| In-app purchases | Yes | No — better |
| Monetization | Free with in-app purchases | Free — better |
| Devices | iPhone, iPad, Apple Watch | iPhone, iPad, iPod, Mac — better |
| Requires iOS | 18.0 | 15.0 — better |
| Further details — not scored | ||
| Size | 95 MB | 259 MB |
| Age rating | 4+ | 4+ |
| Developer | Runloop Ltd | Immersive Gym Company Limited |
Customer experience
Seconds Interval Timer
ImersU
Bugs and requests
Seconds Interval Timer
Reported bugs
2 issues- Timer sometimes stops working unexpectedly
- Issues with restoring purchases on new devices
Requested features
5 requests- Ability to change beep/alert volume independently
- Option to delay transition between intervals
- Sync workouts across devices
- More preset workout templates
- Heart rate monitoring integration
ImersU
Not enough reviews yet to summarise bugs or requests.
In-app purchases
Seconds Interval Timer
- Advanced Version$7.99
ImersU
No in-app purchases
Questions
Is Seconds Interval Timer free?
Is ImersU free?
Which has better reviews, Seconds Interval Timer or ImersU?
Do Seconds Interval Timer or ImersU have ads?
Which is updated more often, Seconds Interval Timer or ImersU?
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