CKcardio

Calorie tracking, a free Pro trial, your sensor recognized instantly at the gym, now in 20+ languages. Train smarter!

CKcardio – Heart Rate Training with Zones CKcardio makes heart rate training simple, precise, and motivating. Whether you're running, cycling, doing HIIT, or training freely — keep your heart rate zones in view and train exactly where it counts. Live heart rate across five customizable training zones Rest, Recovery, Fat Burn, Anaerobic, and Maximum — set the exact heart rate range for each zone yourself, so the app adapts precisely to your fitness level. Support for Bluetooth chest straps and Apple Watch Connect your heart rate strap (e.g. Polar) or use your Apple Watch directly. If you often train in the same place with many sensors nearby — like at the gym — CKcardio remembers your sensor and highlights it the next time you search, so you can find it instantly. Guided and custom training programs Choose from suggested programs or build your own — with as many phases as you like, custom duration, and a target zone for each phase. You can also record a free workout and save it afterward as a repeatable program, with a handy smoothing feature for clean, rounded phase times. Training continues in the background Lock your iPhone or switch apps — your workout and heart rate tracking keep running reliably. An audio cue announces upcoming zone changes, so you don't have to keep checking the screen. A full summary after every workout See at a glance how much time you spent in your target zone, plus average, maximum, and minimum heart rate, and your estimated calorie burn. Your complete training history stays available to review anytime. Saves to Apple Health Your workouts are optionally saved directly to Apple Health, giving you one central view of your fitness. CKcardio Pro CKcardio Pro unlocks all premium training programs, lets you create and import unlimited custom workouts, and adds new programs regularly. Try Pro free — cancel anytime. Available in many languages CKcardio is available in over 20 languages. Download CKcardio now and train smarter with your heart rate as your guide.