# HIIT Timer - Interval Flex — Custom HIIT & Breathwork

> Custom HIIT & Breathwork (iPhone/iPad app by Peter Lebedev.)

- Source: https://appshunter.io/ios/app/hiit-timer-interval-flex/id6596603930 (this page in markdown: same URL + `.md`)
- Developer: [Peter Lebedev](https://appshunter.io/developer/1760407520)
- Category: Health & Fitness, Lifestyle
- Price: $0.99
- Age rating: 4+
- Requires: iOS 17.5 · 2 MB
- Languages: American English
- Released: 2024-08-06
- Data updated: 2026-07-28
- User reviews in markdown: https://appshunter.io/ios/app/hiit-timer-interval-flex/id6596603930/reviews.md

## What is HIIT Timer?

Interval Flex: Advanced Interval Timer

Create complex interval sequences that simple timers can't handle. Perfect for HIIT workouts with group repetitions, breathwork patterns like 4-7-8 breathing, and pyramid training routines.

Why Choose Interval Flex:

- Complex Patterns: Group intervals and repeat sections - ideal for boxing rounds, Tabata circuits, and breathing exercises
- Smart Grouping: Set up sequences like "warm-up, then repeat high-intensity/rest 5 times, then cool-down"
- Breathwork Templates: Pre-built sequences for 4-7-8 breathing, box breathing, and custom patterns
- Template Library: HIIT, Tabata, pyramid workouts, and meditation timers ready to use
- Visual Feedback: See which intervals are grouped and how many repetitions remain
- Multisensory Alerts: Sound, vibration, and visual cues for seamless transitions

Perfect For:
- Complex HIIT workouts with grouped intervals
- Breathwork and meditation sequences  
- Tabata training with custom rest periods
- Pyramid interval training
- Any timing pattern simple apps can't create

Built for users who need more than basic 30-second/10-second timers. If you've been frustrated by simple interval apps, Interval Flex gives you the flexibility to create exactly the sequences you need.

Download now and build the perfect timer for your routine!

## Chart rankings

- #194 in Top Paid · Health & Fitness (US App Store)


## Version history (last 4 releases)

### 1.3 — 2025-09-01

Minor updates, bug fixes.

### 1.2 — 2025-06-25

Fixed bugs
- the screen was dimming even when the setting to keep it on was toggled
- the music was always reduced even when "reduce volume" was not enabled

### 1.1 — 2024-08-21

• Added sequence statistics

### 1.0 — 2024-08-06

No release notes.

## Apps similar to HIIT Timer

| App | Rating | Price | Category |
| --- | --- | --- | --- |
| [Best Interval Timer HD Pro](https://appshunter.io/ios/app/best-interval-timer-hd-pro/id550421056) | 5.0 (1) | $1.99 | Health & Fitness |
| [Interval Timer ▸ HIIT & Tabata](https://appshunter.io/ios/app/interval-timer-hiit-and-tabata/id6469007234) | 5.0 (3) | Free | Health & Fitness |
| [HIIT & Run Interval Timer](https://appshunter.io/ios/app/hiit-and-run-interval-timer/id6749603263) | 5.0 (1) | Free | Health & Fitness |
| [Best Interval Timer Pro](https://appshunter.io/ios/app/best-interval-timer-pro/id545235730) | 4.8 (14) | $0.99 | Health & Fitness |
| [Interval Timer by 7M](https://appshunter.io/ios/app/interval-timer-by-7m/id6460821981) | 5.0 (1) | Free | Health & Fitness |
| [Tabata Timer ·](https://appshunter.io/ios/app/tabata-timer/id1531963107) | 4.7 (1,497) | Free | Health & Fitness |

---

*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-07-28.*