Atapa vs Iris: many presets, or one evening curve?
Choose Iris if you want preset depth and a Windows build. Choose Atapa if you want one bedtime question, readable deep red at 500K, an offline licence and an app tested on an M5 Pro. Iris's pricing page had moved when we checked on 28 October 2026, and Sundown's posts say its Mac build has had no update since 2022.
Kevin Hofmann, maker of Atapa. Updated . We make Atapa. Corrections welcome at hello@atapa.app.
Iris is one of the older screen-warmth apps, with versions for Mac and Windows and a long list of presets and modes. Atapa is new, Mac only, and built around one evening curve. This page is about the differences, with the date each fact was read, and with two facts about Iris we could not pin down.
Side by side
| Criterion | Iris | Atapa |
|---|---|---|
| Price | About $2 a month or $10 to $15 licences; pricing page moved, re-check (2026-10-28) | $12 once, all of your own Macs; 14-day trial without a card; 14-day refund |
| Platforms | macOS and Windows | macOS 14 or later, Apple silicon; Intel not supported in 1.0 |
| M5 Pro | Not stated on its site (2026-10-28); not tested by us | Works, 6500K to 500K on our M5 Pro (2026-10-29, macOS 27.2) |
| Warmest | Not published as a kelvin figure (2026-10-28) | 500K |
| Readable red | Not described (2026-10-28) | Yes, below 1500K |
| Brightness | Software brightness control (2026-10-28, re-check) | Below the lowest brightness step, 5% floor by default |
| Presets | Many | Six built in (Daylight 6500K, Focus 5000K, Evening 3400K, Candle 1900K, Ember 1200K, Midnight 500K), plus your own |
| Licence | Online activation (2026-10-28) | Offline signed key |
| Last Mac update | None since 2022, per Sundown (2026-10-28) | 1.0, 2026-10-29 |
Where Iris leads
Preset depth. Iris has more modes and presets than any other app on our comparison, and it runs on Windows. If you want to tune a dozen situations by hand, it has the knobs.
Two things we could not confirm
Iris’s pricing page had moved when we checked on 2026-10-28, and Sundown’s comparison posts disagree on the figure ($14.99 once on one, a subscription on another). Sundown’s posts also say the Mac build has had no update since 2022. We have not verified either on Iris’s own site, so both rows say re-check. Trustpilot carries complaints about Iris licensing; we link to the source rather than restate a score we have not counted.
Where Atapa differs
One question, “When do you usually go to bed?”, sets the evening: warming starts 30 minutes before sunset, the deepest stop comes an hour before bed, and daylight is back by wake-up. Three intensities, Gentle, Warm and Deep red, end the night at 1900K, 1200K and 500K. Readable red keeps links and icons visible at the bottom of that range.
The licence is an offline signed key; the app has no network code. It was tested on a 14-inch M5 Pro, macOS 27.2, on 2026-10-29, where apps that tint through a gamma table change nothing. Iris’s site does not say whether it is one of them, and we have not installed it there. The check takes a minute and is on the M5 page.
Price
Iris is about $2 a month or $10 to $15 for a licence, to be re-checked on its current page. Atapa is $12 once for all of your own Macs, with a 14-day trial that asks for no card and a 14-day refund. After the trial Atapa keeps working; from day 29 without a key, warmth stops at 2700K and everything else continues.
Choose Iris if
You want preset depth, you are on Windows as well as Mac, and online licence activation is fine with you. Check its current pricing page first, because ours had moved.
Choose Atapa if
You want one evening curve instead of a dozen modes, deep red at 500K that stays readable, an offline licence, and an app with a dated changelog that was tested on an M5 Pro. The comparison table has the whole field.
Questions
Is Iris still maintained for Mac?
Sundown's comparison posts say Iris has had no Mac update since 2022, read 2026-10-28. We have not verified a release date on Iris's own site, and its pricing page had moved when we checked, so re-check before buying. Atapa's changelog is dated and public, and the M5 page carries a dated retest line after each macOS update.
What does Iris cost?
About $2 a month or $10 to $15 licences, read 2026-10-28; Sundown's posts disagree on the figure and Iris's pricing page had moved, so check the current page. Atapa is $12 once for all of your own Macs, with a 14-day trial that asks for no card and a 14-day refund, and no subscription.
Does Iris work on M5 Pro?
Iris's site does not state it, as of 2026-10-28, and we have not installed it on our M5 Pro. On M5 Pro and M5 Max, apps that tint through a gamma table report success and change nothing (Apple bug FB22273730). Atapa was tested on a 14-inch M5 Pro with macOS 27.2 on 2026-10-29 and changed the screen down to 500K.
Which one is private?
Iris activates its licence online, per its site on 2026-10-28. Atapa has no network code at all: the licence key is an offline signed string checked on the Mac, and there is no account, no update check and no analytics. Reviews on Trustpilot mention Iris licensing complaints; we link rather than restate a score we have not counted.
How warm do they go?
Iris does not publish a single kelvin figure; it offers many presets and modes. Atapa goes from 6500K to 500K, with Readable red below 1500K so links stay visible, and three intensities that end the night at 1900K, 1200K and 500K.