# The Quantified Self vs Siftlee

The clearest difference is update cadence: Siftlee at monthly against The Quantified Self's every 7 months. The Quantified Self's advantage is device support (3 vs 1) and iOS requirement (13.0 vs 17.2). On price, ads and in-app purchases there is nothing between them.

Both are free to download. The Quantified Self sells 4 in-app purchases, starting at $1.99 per month and Siftlee sells 3 in-app purchases, starting at $7.99 per 7 days. Whichever you choose, the download price is not the number that matters.

The Quantified Self ships an update every 7 months, Siftlee monthly. The most recent releases landed on November 3, 2026 and November 5, 2026 respectively.

## The numbers

| Metric | The Quantified Self | Siftlee |
| --- | --- | --- |
| Price | Free | Free |
| Positive reviews | 0.0% of reviews | — |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | Every 7 months | **Monthly** |
| Monetization | Freemium | — |
| Size | 39 MB | 34 MB |
| Requires iOS | **13.0** | 17.2 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [Jared Clifton-Lee](https://appshunter.io/developer/1649451005) | [Ainur Corp.](https://appshunter.io/developer/1896573227) |

## What reviewers say

### The Quantified Self

[App page](https://appshunter.io/ios/app/the-quantified-self/id6443804884)

This app helps you manage recurring tasks and habits, prioritizing them by urgency, due date, or importance. It offers automation based on location or NFC tags, performance tracking, and workload adjustment. Organize habits into projects and review your past activities.

**Highlights:** Recurring task management, Habit tracking (good and bad), Automation via location/NFC, Habit organization into projects, Performance tracking over time, Workload adjustment based on bandwidth

**Features:** macOS Compatibility

**In-app purchases (4)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Pro Monthly | $1.99 | per month |
| Pro Quarterly | $5.49 | per 3 months |
| Pro Biannual | $10.49 | per 6 months |
| Pro Yearly | $20.49 | per year |


### Siftlee

[App page](https://appshunter.io/ios/app/siftlee-ai-second-brain/id6768440046)

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Weekly | $7.99 | per 7 days |
| Monthly | $19.99 | per month |
| Annual | $79.99 | per year |


## Frequently asked questions

### Is The Quantified Self free?

The Quantified Self is free to download, with in-app purchases available.

### Is Siftlee free?

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

### Do The Quantified Self or Siftlee have ads?

Neither The Quantified Self nor Siftlee shows ads.

### Which is updated more often, The Quantified Self or Siftlee?

The Quantified Self ships an update every 7 months, and Siftlee monthly. Most recently, The Quantified Self was updated on November 3, 2026 and Siftlee on November 5, 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.*