# Core vs Engineered Strength

The clearest difference is ads: Core at none against Engineered Strength's shown. Engineered Strength's advantage is update cadence (monthly vs every 33 months). On price, in-app purchases, device support and iOS requirement there is nothing between them.

Both are free to download. Core sells 3 in-app purchases, starting at $1.99 per month and Engineered Strength sells 4 in-app purchases, starting at $8.99 per month. Whichever you choose, the download price is not the number that matters.

Core ships an update every 33 months, Engineered Strength monthly. The most recent releases landed on November 3, 2026 and October 30, 2026 respectively.

## The numbers

| Metric | Core | Engineered Strength |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (4 ratings)](https://appshunter.io/ios/app/core-interval-and-hiit-timer/id1562215374/reviews)** | — |
| Number of ratings | **4** | — |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | Yes | Yes |
| Ads | **No** | Yes |
| Update frequency | Every 33 months | **Monthly** |
| Monetization | Freemium | — |
| Size | 9 MB | 90 MB |
| Requires iOS | 15.0 | **14.0** |
| Devices | iPhone, iPod | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Yating Lu](https://appshunter.io/developer/1526204219) | [Raymond Jones](https://appshunter.io/developer/1587907738) |

## What reviewers say

### Core

[App page](https://appshunter.io/ios/app/core-interval-and-hiit-timer/id1562215374)

This app helps you stay focused during workouts by managing intervals, work times, and rest periods with clear visual and audio cues. Save custom routines for HIIT, Tabata, or boxing, and track your training history to monitor progress.

**Highlights:** Customizable interval timers, Audio cues for work/rest phases, Save and reuse workout routines, Visual countdown and color coding, Workout history and trend tracking, Optional Pro features via in-app purchase

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Monthly | $1.99 | per month |
| Yearly | $9.99 | per year |
| Lifetime | $14.99 | one-time |


### Engineered Strength

[App page](https://appshunter.io/ios/app/engineered-strength/id6748325115)

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases (4)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Subscription (Monthly) | $8.99 | per month |
| Subscription (Every 3 Months) | $14.99 | per 3 months |
| Subscription (Yearly) | $24.99 | per year |
| Remove Ads | $7.99 | one-time |


## Frequently asked questions

### Is Core free?

Core is free to download, with in-app purchases available.

### Is Engineered Strength free?

Engineered Strength is free to download, with in-app purchases available.

### Do Core or Engineered Strength have ads?

Engineered Strength shows ads; Core does not.

### Which is updated more often, Core or Engineered Strength?

Core ships an update every 33 months, and Engineered Strength monthly. Most recently, Core was updated on November 3, 2026 and Engineered Strength on October 30, 2026.

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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*