An XDA piece this week made the rounds by pointing out that most Synology owners are using maybe a third of their box. The rest of the ports, the RAM slot that never quite got used, the CPU sitting at 4 percent, all of it is available for jobs that have nothing to do with holding files. Container Manager (Synology’s rebranded Docker) opened that door for DS220+ owners a couple of firmware cycles ago and every DSM release since has widened it. Below are the eight apps we ran on our own DS923+ over the last month, all administered from a Windows or macOS desktop, all doing work that used to want its own machine.
What to look for in a NAS side-service app
The point of adding a service to a NAS is to retire a Raspberry Pi, a mini PC, or a browser tab, not to add another maintenance burden. Five things matter more than any single feature:
- Runs cleanly in a container. Everything below ships as an official image on Docker Hub or GitHub Container Registry, which is what Synology Container Manager reads. If the maintainer only publishes a bare
.deb, skip it. - Passes traffic to a desktop admin UI. You are managing the NAS from a laptop over the LAN. The service needs a web UI or a client that runs on Windows, macOS, or Linux.
- Survives DSM upgrades. Major DSM versions have broken third-party packages in the past. Container-first services survive because the container is the boundary.
- Backs up its own config. Anything with rules, credentials, or automations should let you export the state file so a NAS wipe is a one-hour recovery, not a weekend.
- Runs on the CPU you actually have. DSM Plus and Value boxes ship ARM or low-power x86 chips. LLMs and heavy video transcodes need help; ad-blocking and home automation are fine.
Quick comparison
| App | Best for | License | Runs as | CPU cost |
|---|---|---|---|---|
| Home Assistant | Home automation hub | Open source | Container | Low |
| Portainer | Managing the other containers | Open source | Container | Very low |
| Pi-hole | DNS ad-blocking, LAN-wide | Open source | Container | Very low |
| AdGuard Home | DNS filtering with DoH/DoT | Open source | Container | Very low |
| PhotoPrism | AI photo indexing on-box | Open source | Container | Medium |
| Immich | Google Photos replacement | Open source | Container | Medium-high |
| Jellyfin | Family media server | Open source | Container | Medium (transcode) |
| Nextcloud | Personal cloud, calendars, contacts | Open source | Container | Low-medium |
1. Home Assistant, Best for absorbing every smart-home hub
Home Assistant is what most NAS repurposing conversations end up at. It runs as homeassistant/home-assistant in Container Manager, talks to Zigbee dongles over USB passthrough, and gives you a single dashboard for every light, sensor, and camera you own. The 2026.7 release finally makes voice assistants first-class on ARM-based Synology boxes, so a DS224+ can now serve as both file share and Alexa replacement.
Where it falls short: Zigbee2MQTT still wants a USB dongle plugged into the NAS itself, which is fine on a desktop-adjacent unit but ugly if the NAS lives in a closet. Bluetooth passthrough is worse.
Pricing: Free. A Home Assistant Cloud subscription unlocks remote access without a reverse proxy, at a modest monthly fee.
Download: home-assistant.io
Bottom line: If your NAS has spare RAM and one free USB-A port, this is the first service to install.
2. Portainer, Best for managing the other containers
Portainer CE is the reason non-sysadmins can run seven containers on a NAS without breaking things. It shows every container’s state, logs, resource use, and volumes in one browser tab. Container Manager’s own UI has caught up in DSM 7.3, but Portainer still wins on stack import, GitOps, and the ability to redeploy a broken container without SSH.
Where it falls short: The free tier caps at three environments. That is one NAS, one home lab Pi, and one dev machine, which is enough for most people but not four.
Pricing: Free CE tier is unlimited on a single environment. Business tier starts higher but is only interesting for teams.
Download: portainer.io
Bottom line: Install this second, right after Home Assistant, and use it to install everything below.
3. Pi-hole, Best for DNS ad-blocking on every device
Pi-hole is the classic NAS repurposing win: point the router’s DHCP at the NAS’s IP, and every phone, laptop, and smart TV on the network stops loading ads and telemetry. On a DS920+ with Container Manager, first-boot is under ten minutes. The web dashboard shows query volume in real time, which is the moment most people realise how much background chatter their TV was making.
Where it falls short: Pi-hole is a DNS blocker, not a firewall. Streaming services that hard-code IPs work around it, and mobile apps that use DNS-over-HTTPS bypass it entirely unless you also run a local resolver.
Pricing: Free.
Download: pi-hole.net
Bottom line: Pick Pi-hole if you want the mature stack, block-list ecosystem, and the community that comes with it.
4. AdGuard Home, Best for DoH/DoT-aware DNS filtering
AdGuard Home covers the same job as Pi-hole with two upgrades that matter in 2026: built-in DNS-over-HTTPS and DNS-over-TLS support, and per-client rules that let a phone keep TikTok while a kid’s tablet doesn’t. It also serves as an upstream for Pi-hole if you want both.
Where it falls short: The block-list scene is smaller than Pi-hole’s, and community-maintained subscription lists are less battle-tested for the long tail.
Pricing: Free. AdGuard’s paid VPN and browser products are separate.
Download: adguard.com/adguard-home
Bottom line: Pick this one if the network has kids’ devices or you already run a DoH resolver upstream.
5. PhotoPrism, Best for on-box photo indexing without the cloud
PhotoPrism takes the family photo drive that already lives on the NAS and turns it into a searchable, face-tagged library that behaves like Google Photos, minus the cloud upload. TensorFlow labelling runs on-box, so the phrase “beach photos with the dog, 2024” actually returns results. On x86 Synology units it is fast; on ARM it is slower but usable overnight.
Where it falls short: Import from an existing library is a one-way trip. Once PhotoPrism has claimed the folder as its own, moving photos around outside PhotoPrism confuses the index.
Pricing: Free community edition covers unlimited photos. A modest membership unlocks Places and a few extras.
Download: photoprism.app
Bottom line: Pick this if the goal is a searchable archive that stays on your box.
6. Immich, Best for a phone-first Google Photos replacement
Immich is the newer answer to the same problem, and it shows. Auto-upload from iOS and Android matches Google Photos’ behaviour almost exactly, sharing links work without a subscription, and the mobile app is polished. The trade-off is CPU: face recognition and duplicate detection want more compute than PhotoPrism, and on a Value-tier Synology the initial indexing pass can take days.
Where it falls short: Version 2.x still marks itself as pre-1.0-stable. Major upgrades sometimes need database migrations. Read the release notes.
Pricing: Free and open source.
Download: immich.app
Bottom line: Pick Immich if you want the phone experience and are willing to give the NAS a little more CPU headroom.
7. Jellyfin, Best for a family media server that doesn’t phone home
Jellyfin is the open-source cousin of Plex and Emby, and unlike either, everything runs locally with no account signup and no metered features. Point it at the NAS’s video volume, wait for it to scan, and every TV, phone, and tablet on the LAN can stream from a browser or an app. DLNA works out of the box; hardware transcoding needs an Intel iGPU or a QuickSync-capable Synology unit.
Where it falls short: Live TV and DVR support exist but need a tuner and some setup. The apps are functional but not as polished as Plex’s.
Pricing: Free.
Download: jellyfin.org
Bottom line: Pick Jellyfin if the family media library is worth self-hosting and you’d rather not pay Plex for the good app.
8. Nextcloud, Best for calendars, contacts, and shared documents
Nextcloud is where a lot of Synology owners land after realising DSM’s built-in packages don’t share calendars with a spouse’s iPhone or a coworker’s laptop very well. Contacts, calendars, WebDAV shares, and a docs suite all run in one container. CalDAV and CardDAV subscriptions work with Apple’s built-in Calendar and Contacts apps, and with Thunderbird on desktop.
Where it falls short: Nextcloud gets slower with age. Databases need periodic OCC maintenance, and the AIO all-in-one image is heavier than a hand-rolled compose file.
Pricing: Free for self-hosted. Nextcloud Enterprise is a paid support tier for organisations.
Download: nextcloud.com
Bottom line: Pick Nextcloud when the NAS is replacing more than one Google account, not just Drive.
How to pick the right stack
You are almost never going to run all eight at once, so pick the pain points:
- Ads and telemetry everywhere: start with Pi-hole or AdGuard Home. Fifteen minutes, LAN-wide effect.
- Google Photos frustration: start with Immich. If you want AI search over an archive that’s already sorted, start with PhotoPrism.
- Growing smart-home shelf: start with Home Assistant. Absorb the hubs one at a time.
- Kids and streaming: Jellyfin, plus AdGuard Home for the tablets.
- Escaping Google entirely: Nextcloud handles the calendars and contacts, Immich handles the photos, Jellyfin handles the media, Home Assistant handles the smart home.
Install Portainer before any of the above. Debugging a broken container without it is not a good time.
FAQ
Can a DS220+ or entry-level Synology run all of these?
Not comfortably. Pi-hole, AdGuard Home, Home Assistant, Portainer, and Nextcloud (with a modest user count) fit inside 2 GB of RAM and low CPU headroom. Immich and PhotoPrism want more RAM and periodic CPU spikes. Jellyfin transcoding wants an iGPU or you accept 480p direct-play. Plus and higher units handle the full stack; Value units want a subset.
Do these break DSM updates?
Container-based services do not, in practice. DSM updates the OS and Container Manager; the containers keep running with their own images. Native Synology packages (the older SPK ecosystem) are riskier and worth avoiding when a container image exists.
Is USB passthrough safe on a Synology?
For Zigbee dongles and small USB devices, yes, if the NAS is on a UPS and you are comfortable rebooting occasionally. DSM 7.3 handles USB removal and reattachment more gracefully than 7.1 did.
How do we handle backups for all this container state?
Snapshot the volume that holds container config folders, either with Synology Snapshot Replication or Hyper Backup. Home Assistant and Nextcloud both have their own backup exports too; use both belt and braces.
Which one gives the biggest quality-of-life gain first?
Pi-hole or AdGuard Home. The network gets faster, ads stop loading on every device, and it takes fifteen minutes. Home Assistant is a slower burn but pays off over months.
