KaiOS
Ranked 14 of 14 mobile operating systems by recommenders
Simple feature-phone OS built on Firefox OS and AOSP, with a web framework for custom apps; critics note a small app store missing some needed apps like messaging.
Simple feature-phone OS built on Firefox OS and AOSP, with a web framework for custom apps; critics note a small app store missing some needed apps like messaging.
7 people gave an opinion
- recommend it
- 5
- criticize it
- 2
- approval share
- 71%
Recommended in 5 of 13 months
- November 2025: not recommended
- December 2025: not recommended
- January 2026: not recommended
- February 2026: not recommended
- March 2026: recommended
- April 2026: not recommended
- May 2026: recommended
- June 2026: not recommended
- July 2026: not recommended
- August 2026: recommended
- September 2026: recommended
- October 2026: recommended
- November 2026: not recommended (month in progress)
Why it doesn’t carry the badge
- 5 people recommend itNeeds 10 or more, not met.
- 2.5 recommenders for every criticNeeds 2 to 1 or better, met.
- Recommended in 5 of 13 monthsNeeds 4 or more, met.
The same three rules apply to every product, and the badge can’t be bought. How the badge works
What people say about it
The reasons people give, with the number of comments that give each one. Open a reason to read what they said.
Why people recommend it
Each mark is one comment
Built on Firefox OS and AOSP
“KaiOS, based on Android Open Source Programme (AOSP) and the former Firefox OS usually further simplified.”
Comment from 29 May 2026 in “Can these dumbphone evangelists convince you to dump smartphones?” “it went on to be the insanely successful KaiOS based on the source code”
Comment from 31 Aug 2026 in “Google Has Removed MV2 Extensions from the Chrome Web Store, Including UBO” Web framework for making your own apps
“An undiscovered country with just a few thousand apps in their store, and a web framework to make your own.”
Comment from 22 Sep 2026 in “Apple has added persistent 'ads' to iOS, and it's driving users crazy” Widely successful on simple phones
“it went on to be the insanely successful KaiOS based on the source code”
Comment from 31 Aug 2026 in “Google Has Removed MV2 Extensions from the Chrome Web Store, Including UBO”
What people warn about
Each mark is one comment
Missing some apps, such as messaging
“they don't support the messaging app I need”
Comment from 23 Oct 2026 in “Your Phone Is About to Stop Being Yours: 70 Days Until Lockdown” Criticized as awful by one user
“KaiOS was honestly awful.”
Comment from 4 Jun 2026 in “Dumbphone 2”
Other mobile operating systems people recommend
The four most recommended other mobile operating systems, with the same counts for each, so you can compare like for like. The tick on each bar marks the 2 to 1 line the badge needs.
| Product | Recommend | Criticize | Approval | Months | Owned | Badge |
|---|---|---|---|---|---|---|
| GrapheneOS | 895 | 312 | 74% | 13 | 1 yr87 owners | Approved |
| Android | 372 | 694 | 35% | 13 | 10 yrs26 owners | — |
| Apple iOS | 308 | 841 | 27% | 12 | 3 yrs40 owners | — |
| LineageOS | 186 | 66 | 74% | 13 | 10 yrs8 owners | Approved |
| KaiOSThis page | 5 | 2 | 71% | 5 | — | — |
What people said
5 of the 7 comments that mention it, newest first. Each links to the original comment.
“they don't support the messaging app I need”
“An undiscovered country with just a few thousand apps in their store, and a web framework to make your own.”
“it went on to be the insanely successful KaiOS based on the source code”
“KaiOS was honestly awful.”
“KaiOS, based on Android Open Source Programme (AOSP) and the former Firefox OS usually further simplified.”
Counts come from 1,795,640 Hacker News comments, November 2025 to November 2026. How we count. Report a mistake.