Control4 OS versions: OS 3 vs X4

What changed between Control4 Smart Home OS 3 and X4 (OS 4.x) that matters to dealers, plus upgrade cautions. Always read the current release notes on the dealer portal before upgrading; requirements change between point releases.

Naming: OS 3, X4, OS 4.0, 4.1, 4.2

• Control4 Smart Home OS 3 (3.0 in 2019 through 3.4.x in 2024) introduced the modern Control4 app experience and was the platform for most installed systems.
• X4 is the brand name for OS 4. X4 and OS 4.0 refer to the same release (initial release April 2025). OS 4.1 followed in September 2025. OS 4.2 releases followed in 2026.
• Composer Pro builds were tied to OS versions for years. Starting with OS 4.1, Composer Pro is decoupled from the OS and uses date-based versions (for example a 2026.x build), with an OS Management Package that matches the controller's OS. Pick the Composer build that supports the OS you are connecting to.

Notable OS 3.x milestones

From Control4's release history, the dealer-relevant points:

• 3.1.x: Composer Pro version independence, Google Assistant, Intercom Anywhere expansion; 3.1.1 removed default passwords; 3.1.3 added the Access agent.
• 3.2.x: video doorbell, OS 3 app with intercom, History view; T4 touch screen support (3.2.1); OvrC Pro on controllers, ambient light sensor sources and followers, ZigBee Health and Device Logs (3.2.2); MultiDisplay Manager, EQ controls, driver search, connection filters, Dynamic AV buttons, Night Mode (3.2.3 and 3.2.4).
• 3.3.x: CORE controllers, colored lighting, remote connection screen, ZigBee configuration change (3.3.0); Z-Wave v2, lighting scenarios (3.3.1); Halo remotes and other additions (3.3.2).
• 3.4.x: system notifications (3.4.0); maintenance releases through 3.4.3 (late 2024).

What X4 (OS 4.0) changed

• New user interface and mobile experience with a customizable Home Screen and widgets.
• Customizable Routines that homeowners edit in the app. The Routines agent is required on X4.
• In-app voice management with HomeKit (Siri setup and control from the Control4 app).
• AirPlay 2 support on supported audio hardware (for example Triad SA1).
• Requires a supported controller (CORE, CA, or EA series) and the new Control4 app.

Dealer impact: customers can now build their own routines and arrange their own home screen. Agree with the customer on who owns which automations so Composer programming and app routines do not fight.

Hardware that reached end of support with X4

OS 4 is the terminal release for:

• T3 touch screens (in-wall and tabletop, 7 and 10 inch).
• Gen 1 and Gen 2 dimmers, switches, and keypads.
• The On-Screen Display (OSD) on EA-1, EA-3, and EA-5 controllers. The controllers themselves stay supported; only the on-screen interface goes away.

OS 4.1 notes state these platforms no longer receive software updates or technical assistance. Customers with this hardware should plan replacement (Gen3 or Lux lighting, T4 or newer touch screens).

OS 4.1 and later changes

• Driver Migration agent with a Light/Keypad Migration Wizard: moves Gen1, Gen2, and Gen3 lighting and keypads to Lux, carrying device properties, lighting scenes (not flashing scenes), keypad button configuration, connections, and programming. Add the Lux devices to the project first. It has an engraving-only step for Gen3. Migrated devices are new devices hidden from Navigator, so check visibility and engravings afterward.
• Composer Pro decoupled from the OS with date-based versioning.
• Fixes listed include scheduler events not firing consistently on X4, required agents not auto-added on OS update, an advanced lighting scene edit that could crash Director, and AV pathing issues.
• Upgrading to OS 4.1 required the system to be on OS 4.0 or higher, and the 4.1 notes list an active Connect subscription. Later Snap One announcements describe Connect as optional for X4 systems. Check the current requirements for the release you are installing.

Exact details of OS 4.2 changes: check the 4.2 release notes on the dealer portal. This guide does not list them.

Upgrade cautions from OS 3 to X4

Before:

1. Read the release notes and any "read this first" documents for the target release.
2. Confirm the system meets the minimum starting version (X4 required a late OS 3.4 release as the starting point; verify the current minimum) and the controller is a supported model.
3. Verify account linking: the customer account, the dealer of record, and OvrC (if used) all point to the right system. Only technicians assigned on the dealer account can connect locally in Composer Pro.
4. Inventory end-of-support hardware (T3s, Gen1/Gen2 lighting, EA OSD use) and tell the customer what changes.
5. Check every third-party driver for X4 compatibility with its developer. Update drivers before or right after the OS update.
6. Back up the project (File > Back Up As with a date, plus a cloud backup).
7. Make sure all devices are online so they can take firmware.

During: expect Composer to disconnect and audio to stop while Director updates. Watch Update Manager to the finished message.

After:

1. Confirm firmware versions in Network Tools.
2. Confirm required agents (Routines, Home Screen) are present.
3. Test each room's Watch and Listen, lighting scenes, schedules, and key programming.
4. Refresh Navigators and confirm the app on the customer's phones.
5. Back up again on the new version.

Driver compatibility across OS versions

• Each driver declares a minimum OS version. Composer will not load a driver that needs a newer OS than the controller runs.
• Drivers built and tested on X4 may not be confirmed on OS 3. Check the developer's compatibility notes.
• Some driver API behavior differs between OS versions (for example how some Lua calls return data). A driver that worked on OS 3 can misbehave on X4 until the developer updates it.
• When a customer's system cannot be upgraded (end-of-support hardware they will not replace), pin driver versions that are known to work on their OS and keep the files in the project records.

Should this customer upgrade?

Upgrade when: the customer wants the X4 app features, the hardware is supported, third-party drivers are confirmed compatible, and you can schedule a visit or a remote window with time to test.

Wait when: the site depends on T3 touch screens or Gen1/Gen2 lighting that the customer will not replace yet, critical third-party drivers are not confirmed on X4, or the network has known issues you have not fixed. An OS upgrade on a shaky network multiplies service calls.

Treat every OS upgrade as a scheduled service event, not a background task: back up, update, test, back up.