Why is my Shopify store slow?

A shopper opens your denim jacket on their phone

Why is my Shopify store slow? Shopify itself is rarely the slow part. More often it is something you switched on in your theme, like a chat bubble that floats in the corner or a bit of an app’s code the shopper never sees, and on a phone it can reach the screen before your product photo does. Shopify keeps all of those switches in one list in the theme editor, and calls each one an app embed.

Let’s stay with one product the whole way through. Someone on their lunch break taps your ad for the denim jacket, the washed one with the copper buttons. They want to see the jacket: the colour of the wash, the stitching, how it sits on the shoulders.

Before the photo appears, a chat bubble slides into the corner, or a popup asks for their email, and for a moment that is all they have to look at. The jacket photo should be first, because it is the reason they tapped. The chat and the popup can turn up a moment later and still do their jobs.

So what is Shopify already doing for that jacket? Quite a lot. Shopify’s guide to site speed says your store already runs on fast servers around the globe, sends copies of the store from computers near the shopper, which is what people call a CDN, and shrinks the jacket photo for each screen on its own. You do not need to buy any of that.

The same guide names the biggest things that slow a store down: your theme, the apps you have installed, and any extra code someone pasted in, including a tag manager, which is a box that loads other companies’ tracking tags. This post stays with the apps, because the ones that float over the jacket are switched on in one list you can open today.

What an app embed is, and how its switch works

When you installed the chat app, it did not drop a box onto the jacket page, the way a size chart app does. It added a switch to your theme. Shopify’s notes on theme apps put every one of those switches in the same panel in the theme editor, called App embeds, where you turn each one on or off and open its settings.

Each switch has two positions. When it is on, the app’s program travels with the page to the shopper’s phone. When it is off, the program stays behind, and the app itself stays installed in your admin, ready to switch back on.

So why would a little bubble in the corner hold up a whole jacket? The phone has one lane for drawing the page and running programs. Shopify’s notes on theme performance say the program from every installed app competes in that lane with the page it is trying to draw.

When the chat’s program gets in first, the jacket waits behind it, even though the bubble is small and the photo fills the screen. The shopper sees the corner of the page doing something while the middle of it, the part they came for, is still empty.

The switches you cannot see work the same way. A tracking app that went in as an embed draws nothing at all, so it is easy to forget it is there, and it still asks the phone for time while the jacket is loading.

Why the forgotten switch is the one to turn off

It is easy to end up with a switch that made sense once. You tried a chat app for a sale weekend, then moved questions back to email. You ran a spin-to-win popup over the holidays. The app is still installed, the switch is still on, and every shopper who opens the jacket still gets its program.

Shopify’s guide to site speed says to take off the apps that are not essential, because too many of them load extra files on every page. Ask that of every switch on the list. Is anyone still using this chat, and did that popup sign anyone up since the holidays?

The chat is there for the shopper with a question. The jacket photo is there for every shopper who taps the link. When nobody is asking the chat anything, the switch is making every visitor wait for a job it no longer does.

I know what you’re thinking. You still want the chat, and you are not about to uninstall it. You do not have to. Turning a switch off is not uninstalling, and if you answer that chat every day, leave it on, because this decision is only for the switches nobody is using.

That leaves two kinds of switch. The forgotten one you can turn off today, which costs you nothing and gives the jacket the screen back. The one you want to keep is still in front of the photo when you are done, and that one needs a different fix.

Turn off the switch, then open the jacket on your phone

Here is the check, in the order you click. It takes a couple of minutes on a laptop. Shopify’s notes on theme apps put the switches in the theme editor’s App embeds section, where you turn each one on or off.

1. From your Shopify admin, go to Online Store, then Themes.

2. Find the theme your store is using, and then click Edit theme.

3. Open App embeds. Each switch is listed there, and you can open its settings.

4. Beside the embed that is not earning its place, turn it off.

5. Click Save, so the change reaches the store your shoppers see.

6. Open the live denim jacket on your phone, from a normal link the way a shopper would, rather than from the preview in the editor.

Watch the first few seconds on the phone. If the jacket photo is the first thing you see, and the chat or the popup turns up after it, you can stop here.

And the chat you kept? If it is still in front of the jacket, that is the job Whoosh takes on. Smart App Loading puts the programs from your other apps in order behind the product photo, so the chat, the popup, and the reviews still load, just after the jacket is on screen. It works with 20+ known apps, shows you which ones it found on your store, and does not uninstall any of them or copy your theme.

Smart App Loading is US$99 a month on the Shopify App Store, with a 7-day free trial and no code to write. Once it is on, open the jacket on your phone again, then tap the chat bubble and send yourself a message, so you know it still opens.

If the switches are sorted and the jacket photo itself is still slow, or the page stays white before any layout appears, that is a different wait, either which copy of the photo the theme asks for or the design loading before anything else, so check that one and then come back to this list.

Every app you install from now on can add a new switch to App embeds. Open the list again the day you add one, and leave on only the switches somebody uses.