Comparison

RSP App vs CHASKi.fit

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

Head to head
About

RSP App

Features
Read full description

RSP APP: High-Performance Training Application The digital extension of the Isoinertial (Eccentric) machines manufactured by einercial.com. RSP APP measures training performance in real-time via a Bluetooth streaming data connection. Performance is measured in power output (watts) and work cycles. Using these two indicators, the app provides users with valuable insights into their machine usage and performance. Users can save and review their training history. The app includes presets for each of the three machines that feature the hardware connection terminal. HOW DOES IT WORK? The system consists of a hardware component connected to the machine (compatible with any model from the manufacturer). This hardware is a rotary encoder, a high-tech device capable of registering up to 1,000 points per rotation of the yo-yo. On the other end, the app receives and processes this data. Let’s dive into the details: THE ROTARY ENCODER • Completely wireless: The RSP encoder is designed with ergonomics and usability in mind. • Long-lasting battery: It features a rechargeable battery with a standard female mini USB connector for charging with any standard mobile charger. EASY INSTALLATION ON RSP MACHINES: JUST CONNECT AND GO The encoder fits all RSP machines. It attaches using three small standard screws. DATA TRANSMISSION VIA BLUETOOTH The connection to the app is through Bluetooth, ensuring a fast and reliable link. The encoder sends data to the app, allowing you to move up to 15 meters away—ideal for trainers. BASIC WORKFLOW WITH THE APP 1. CONNECT THE APP TO A MACHINE Once the encoder is turned on and Bluetooth is enabled on your phone, the app will detect the signal and prompt you to select a machine. It will also request mass (weight) configuration. Once both are confirmed, you can start training. 2. START TRAINING: COACH MODE Another option, particularly useful for personal trainers or gym instructors, is to register multiple athletes in the same session. You can add as many as needed, recording the strength values for each individual and creating a comprehensive session history. 3. REAL-TIME PERFORMANCE MONITORING The app displays the machine and its selected mass configuration on the screen. It also shows real-time performance data, including power per cycle, time, power output, and other session details—all live on your screen. OTHER TRAINING MODES FOR HIGH-PERFORMANCE CIRCUITS Once familiar with the machine and its limitations, you can choose a training mode based on power ranges. The app leverages session history to provide data on strength ratios, best performances, and their correlation with lower scores. With this information, you can select training modes based on maximum and minimum power ranges, challenging yourself to stay within the interval. RSP Inertial Performance | Tools for Athletes

About

CHASKi.fit

Features
Read full description

Elevate your training with the CHASKi app, the perfect companion for athletes and fitness enthusiasts seeking to optimize performance. Packed with cutting-edge features, this version brings a revamped Ramp Test system, offering programmed protocols and enhanced data capture for simpler testing. The update lets you rename your CHASKi, track different sport types, and see metrics such as VTs and VO2max directly from your mobile app. Stay ahead of your goals with frequent updates that will continuously introduce new features and refine your user experience. CHASKi is your trusted partner in breathing better, training smarter, and pushing limits. Download now and redefine the way you optimize your fitness!

Screenshots

RSP App4 screens
CHASKi.fit4 screens

Verdict

The call

The clearest difference is iOS requirement: RSP App at 13.0 against CHASKi.fit's 16.0. On price, update cadence, ads and in-app purchases 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. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

Both ship on a similar rhythm, roughly every 2 months. The most recent releases landed on September 26, 2026 and September 19, 2026 respectively.

Scorecard1 real difference · 5 level
RSP App versus CHASKi.fit: the parameters behind the verdict, then further details
ParameterRSP AppCHASKi.fit
PriceFreeFree
Update frequencyEvery 2 monthsEvery 2 months
AdsNoNo
In-app purchasesNoNo
DevicesiPhone, iPad, iPod — betteriPhone, iPad
Requires iOS13.0 — better16.0
Further details — not scored
Size23 MB28 MB
Age rating4+4+
DeveloperInercial Performance Sl.IC Innovations

In-app purchases

None

RSP App

No in-app purchases

None

CHASKi.fit

No in-app purchases

Questions

Is RSP App free?
RSP App is free to download, with no in-app purchases.
Is CHASKi.fit free?
CHASKi.fit is free to download, with no in-app purchases.
Do RSP App or CHASKi.fit have ads?
Neither RSP App nor CHASKi.fit shows ads.
Which is updated more often, RSP App or CHASKi.fit?
RSP App ships an update every 2 months, and CHASKi.fit every 2 months. Most recently, RSP App was updated on September 26, 2026 and CHASKi.fit on September 19, 2026.

Other comparisons