# Backlog by Time Engine vs Dopamine

The clearest difference is in-app purchases: Backlog by Time Engine at none against Dopamine's 2. Backlog by Time Engine also leads on iOS requirement (16.4 vs 18.0). On price, update cadence, ads and device support there is nothing between them.

Both are free to download. Dopamine sells 2 in-app purchases, starting at $4.99 per month. Backlog by Time Engine asks for nothing beyond the download.

Backlog by Time Engine ships an update every 3 weeks, Dopamine every 5 weeks. The most recent releases landed on September 19, 2026 and August 28, 2026 respectively.

## The numbers

| Metric | Backlog by Time Engine | Dopamine |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | **Every 3 weeks** | Every 5 weeks |
| Size | 3 MB | 13 MB |
| Requires iOS | **16.4** | 18.0 |
| Devices | iPhone | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [100-8 Studio](https://appshunter.io/developer/1436780503) | [Ksenia Shubova](https://appshunter.io/developer/1877285298) |

## What reviewers say

### Backlog by Time Engine

[App page](https://appshunter.io/ios/app/backlog-by-time-engine/id6470202026)

**Features:** macOS Compatibility

**In-app purchases:** none


### Dopamine

[App page](https://appshunter.io/ios/app/dopamine-adhd-to-do-chat/id6759327169)

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Dopamine Monthly | $4.99 | per month |
| Dopamine Yearly | $39.99 | per year |


## Frequently asked questions

### Is Backlog by Time Engine free?

Backlog by Time Engine is free to download, with no in-app purchases.

### Is Dopamine free?

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

### Do Backlog by Time Engine or Dopamine have ads?

Neither Backlog by Time Engine nor Dopamine shows ads.

### Which is updated more often, Backlog by Time Engine or Dopamine?

Backlog by Time Engine ships an update every 3 weeks, and Dopamine every 5 weeks. Most recently, Backlog by Time Engine was updated on September 19, 2026 and Dopamine on August 28, 2026.

---

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