The short answer
CasaOS and ZimaOS come from the same company, IceWhale, and look alike, but they are different kinds of software. CasaOS is a dashboard you install on Linux you already run. ZimaOS is a complete NAS operating system that replaces what is on the disk, and it is where IceWhale's development now goes.
Pick ZimaOS for a dedicated x86 machine whose main job is storage: RAID, several user accounts, backup jobs and remote access are built in, and it is actively developed. Pick CasaOS if the machine already runs Debian, Ubuntu or Raspberry Pi OS with other things on it, if it is an ARM board such as a Raspberry Pi, or if you want no licence limits at all. Keep in mind that CasaOS has had no release since December 2024.
CasaOS and ZimaOS side by side
| CasaOS | ZimaOS | |
|---|---|---|
| What it is | A dashboard installed on existing Linux | A complete NAS operating system |
| Installs on | Debian, Ubuntu, Raspberry Pi OS, Armbian; amd64, arm64 and armv7 | x86-64 machines with UEFI; replaces the OS |
| Underlying system | Your normal Linux, with apt and SSH | A managed, read-only system; SSH and a web terminal in Developer Mode |
| App store | About 180 apps in the official store, plus community stores | Hundreds of apps, third-party stores, and Docker Compose import |
| Drive redundancy | None of its own; use Linux tools | RAID 0, 1, 5 and 6, with ZFS as an option |
| User accounts | One | Several, with per-user Samba permissions |
| Backups | None built in | Backup jobs from cloud, USB, network or internal drives, to one or two destinations |
| Remote access | Install and configure an app such as Tailscale yourself | ZimaClient, a peer-to-peer encrypted connection |
| Price | Free, Apache 2.0 open source | Free up to 4 disks and 3 users; Plus is a one-time $29 |
| Development | Last release v0.4.15, December 2024; app store still updated | Regular releases: 1.7.1 in August 2026, 1.8 in beta |
Checked against CasaOS v0.4.15, ZimaOS 1.7.1 and IceWhale's documentation and pricing pages in September 2026. The CasaOS app count is the number of apps in the official CasaOS-AppStore repository at that time.
Same family, different jobs
IceWhale built CasaOS as a friendly layer for any Linux machine, its own ZimaBoard included: one command, and you have an app store, a file browser and widgets. It left the operating system alone, which is why it runs on almost anything, from 32-bit ARM boards to x86 servers.
ZimaOS takes the same look and turns it into a NAS operating system for IceWhale's ZimaCube and for other x86 hardware. Because it owns the whole system, it can manage disks and RAID, users and permissions, backups and remote access, things a dashboard on someone else's Linux can only partly do. IceWhale now describes CasaOS as a community project and points people who want an integrated NAS to ZimaOS.
Where ZimaOS is ahead
- Storage. RAID 0, 1, 5 and 6 from the interface, with ZFS available for snapshots and checksums. CasaOS leaves this to you.
- Several users. Separate accounts for family members with their own read and write permissions on shares.
- Backups. Jobs from any source (cloud drives, USB, network, internal) to one or two destinations, which makes a 3-2-1 setup possible from the UI.
- Cloud drives. Google Drive, Dropbox and OneDrive connections, with iCloud added in the 1.8 beta along with a photo library.
- Remote access through ZimaClient without port forwarding.
- It is maintained. ZimaOS ships regular releases with new features and security fixes.
Where CasaOS still makes sense
- Raspberry Pi and other ARM boards. ZimaOS supports x86-64 only. CasaOS runs on arm64 and even 32-bit armv7.
- Keeping your OS. CasaOS sits on Debian or Ubuntu, so apt, SSH, cron and anything else you run stay exactly as they were. ZimaOS is a managed, read-only system where shell access is a developer option.
- No limits. CasaOS has no disk or user limits and no paid tier. ZimaOS's free edition stops at 4 disks and 3 users; beyond that you need Plus, bound to one device. IceWhale's own ZimaBoard, ZimaBlade and ZimaCube include Plus.
- Lightness. CasaOS is a few small services; nothing about your system changes if you remove it.
What the ZimaOS licence limits mean in practice
ZimaOS became a free-plus-paid product with version 1.5. The free edition includes the core NAS features, apps and remote access, and caps you at 4 disks and 3 users. ZimaOS Plus removes both caps for a one-time $29, with no subscription, and IceWhale has said Plus will never become one. People who upgraded from older versions before June 30, 2026 were given Plus for free; new installs on non-Zima hardware now buy it.
For a typical two-drive home NAS used by a couple, the free edition is enough. A six-bay build, or a household of four with separate accounts, will need Plus. That is still cheap next to Unraid's licence, and our home server OS comparison lists what the other options cost.
Moving from CasaOS to ZimaOS
IceWhale does not document an in-place upgrade from CasaOS to ZimaOS, and since ZimaOS replaces the operating system, plan for a fresh install:
- 1.Note the apps you run in CasaOS and where each keeps its data, usually under
/DATA/AppData. - 2.Copy that data and your files under
/DATAto a separate disk or another machine. - 3.Install ZimaOS on the boot drive of an x86-64 machine.
- 4.Reinstall your apps from the ZimaOS store, or import their Compose files, and point them at the copied data.
- 5.Check each app with a database, such as Immich or Nextcloud, against its own backup and restore instructions before you delete anything.
If the machine is a Raspberry Pi, ZimaOS is not an option, and your choice is between staying on CasaOS or moving to another dashboard on Raspberry Pi OS.
A third option: keep your Linux, keep the CasaOS store
If you want CasaOS's model, a dashboard on your own Linux with the CasaOS app store, but with active development, that is what Homeio, the project behind this site, does. Its default catalogue is the CasaOS store, it keeps app data in the same /DATA/AppData folders, and it installs on Debian, Ubuntu or Raspberry Pi OS, including on a Pi. It adds scheduled tasks, weekly backups, two-factor login, disk partitioning and formatting, Samba shares, and Tailscale and Cloudflare Tunnel in Settings. It is MIT licensed with no paid tier.
What it does not do is replace a NAS OS: Homeio has one user account, no RAID manager and no ZFS tooling. If redundant storage and family accounts are the goal, ZimaOS or another NAS OS is the better fit. Our ZimaOS alternative and CasaOS alternative pages go through the details.
Which one should you choose?
- Dedicated x86 NAS with two or more drives: ZimaOS.
- Family members who need their own accounts and shares: ZimaOS.
- A ZimaCube or ZimaBoard: ZimaOS, with Plus included.
- Raspberry Pi or another ARM board: CasaOS, or a maintained dashboard such as Homeio on Raspberry Pi OS.
- Machine already runs Linux with other services: CasaOS or Homeio.
- Existing CasaOS server that works: keep it for now, and plan your move before the next rebuild.
- Still undecided between NAS operating systems: see CasaOS vs Umbrel and our home server OS comparison.