Theme app add-ons: a Shopify gallery bundled with the theme

On 28 October 2026 Shopify told theme developers they can bundle a storefront app with a theme on the Theme Store. The listing shows the app next to the theme, with its price, and a merchant can install both in one flow. Shopify's own examples are product configurators, subscriptions and filtering, but a gallery or lookbook is an obvious candidate, because every theme listing already shows off photography and a built-in gallery is an easy upsell. So it is worth being clear, before the first themes with add-ons appear, about what a bundled gallery is, what it is not, and which questions decide whether it is a good idea for your store. The short version: an add-on is still a separate app with its own bill and its own data, and the questions you would ask any gallery app still apply, plus one new one about what happens when you leave the theme.

What Shopify actually announced

The changelog entry is short. A theme developer who also owns a published storefront app can attach that app to a theme listing in the Partner Dashboard. The app must be built with theme app extensions, meaning it adds app blocks to the theme editor rather than injecting scripts. Merchants see the add-on on the theme's page with pricing, media, a name and a subtitle, and installing the theme offers to install the app in the same flow. The rules Shopify published: the app has to be published before it can be attached, it can be listed or unlisted on the App Store, the same partner organisation must own both the theme and the app, and there is one add-on per theme, though a developer can reuse the same app across all of their themes.

Two things in that list matter more than they look. First, the app can be unlisted. An unlisted app is a real, reviewed app, but it does not appear in App Store search and you will not find a public review history for it, so the theme listing may be the only place you ever see it described. Second, the billing goes through Shopify App Pricing, which is the same system every other app uses. A bundled app is not a feature of the theme; it is an app that happened to be offered on the same page.

Three places a gallery can come from

Once add-ons exist, a theme can give you a gallery in three different ways, and they behave differently when something changes.

The first is a native theme section, the Collage, Multicolumn or Image-with-text style blocks every theme ships with. Those are theme code, and the images you pick are stored in the theme's template JSON. They cost nothing extra and they are gone the day you publish a different theme, because the next theme has its own templates. Good for a hero banner, painful for a two-hundred-photo lookbook you curated by hand.

The second is a theme app add-on. It is an app, so its data lives wherever that app chooses to put it: in your store as metaobjects or metafields, on the developer's servers, or split between the two. It is installed separately, billed separately and can be uninstalled separately. It was designed to look right in its parent theme, which is the whole pitch, and it may or may not look right in anyone else's.

The third is an independent gallery app you install from the App Store, which is what Snug Gallery is. It is also a theme app extension, so it appears in the theme editor as an app block like an add-on would, but it is built to sit in any theme that supports app blocks, which is every Online Store 2.0 theme. The galleries are app-owned metaobjects in your store and the media is in your Files, so changing themes means adding the block again, not rebuilding the content. The details of that split are in what happens to your galleries when you switch themes.

The new question: what happens when you leave the theme

Most stores change theme every two or three years. A gallery add-on that was attached to the theme you bought in 2026 is still installed in 2028 when you move to a theme from a different developer. Technically it keeps working; an app does not uninstall itself because a theme was unpublished. But a block built to match one theme's spacing, typography and colour scheme may look like a guest in the next one, and the developer has no particular reason to keep it looking good in a competitor's theme. So ask, before you lean on it: does this app work in other themes, is that stated anywhere, and is it listed on the App Store on its own, which is a reasonable signal that it is meant to.

There is also the reverse case. If you leave the theme but want to keep the add-on because the content is in it, you are now paying for an app you chose for a theme you no longer run. If the app stored your gallery on the developer's servers rather than in your store, moving the content elsewhere means exporting, if there is an export, or re-uploading. The questions in who owns your gallery images apply to add-ons exactly as they apply to any other app, and they are easier to ask before you upload three hundred photos than after.

Billing: one page, two charges

A theme is a one-off purchase. An app on Shopify App Pricing is usually a recurring charge, and the listing will show it as such. The single install flow makes it feel like one decision, but your Shopify bill will show two lines: the theme once, and the app every month or year for as long as it is installed. That is not a criticism, it is just how the two products are sold, and it is worth noticing because a theme that looks cheaper than a competitor's might be making up the difference on the add-on. If you do not need the add-on, you can install the theme without it; the flow offers the app, it does not require it.

Uninstalling the add-on later works like uninstalling any app, including the detail that charges stop at the end of the current billing cycle rather than instantly. How app charges work after uninstall covers that for Shopify apps in general.

What this changes for Snug Gallery

Honestly, not much, and that is the point of writing it down. Snug is not a theme add-on and will not become one, because we do not sell a theme. It is an App Store app that renders through a theme app extension, the same mechanism add-ons use, so anything a bundled gallery can do in the theme editor, an independent block can do too: app blocks in sections, theme-editor settings, the preview updating as you type. The differences are the ones above, and they are about where the data lives and what the app is designed to survive, not about what the block can draw.

If a theme you are considering ships with a gallery add-on, there is nothing wrong with trying both. Add the bundled block to one page and a Snug block to another in the unpublished theme and compare them on a phone. The block settings in the theme editor reference are the full list of what Snug exposes, so you can tell quickly whether the add-on has a layout or a behaviour that Snug does not, and the other way round.

A checklist for a bundled gallery

Open the add-on's own App Store listing, if it has one. If it is unlisted, ask the theme developer why, and treat the lack of a public review history as a missing data point rather than a red flag on its own.
Find out where the photos and the gallery layout are stored. In your store's Files and metaobjects is the answer you want; on the developer's servers is a dependency you should price in.
Ask whether the app works in themes other than the one it ships with, in writing.
Read the price as a recurring line on your Shopify bill, separate from the theme, and check what the free tier, if any, includes.
Install the theme into your library without publishing it, add the bundled block and any alternative to a test page, and compare them on a phone before deciding.
Run the same checks you would on any gallery app: the is this app abandoned list is a good one.

Frequently asked questions

Does a theme app add-on get uninstalled when I change themes?

No. It is a separate app with its own install and billing. Changing or deleting the theme does not remove it, and its charges continue until you uninstall it from the Apps page.

Can I install the theme without the add-on?

Yes. The combined flow offers the app alongside the theme; it does not make the theme depend on it. You can also install the add-on later if you decide you want it.

Is Snug Gallery a theme app add-on?

No. Snug Gallery is an independent App Store app that uses a theme app extension, so it appears in the theme editor as an app block in any Online Store 2.0 theme. Its galleries are stored as metaobjects in your store and its media in your Files.

Will a bundled gallery look right in a different theme?

Sometimes. It is a theme app extension, so it will render, but it was styled for its parent theme. Ask the developer whether other themes are supported and test it in the unpublished theme before relying on it.