Confirm the gap is real
In Shopify Analytics, break conversion rate down by device. Some gap between desktop and mobile is normal, people research on phones and buy on laptops. But if mobile is half or worse, and most of your traffic is mobile, that's not normal, that's money leaking.
Write both numbers down. This is the thing you're trying to move.
Above the fold is doing too much
On a phone screen, the first thing a visitor sees is tiny and precious. If it's a giant hero image, a cookie banner, a discount popup and a sticky bar all at once, the actual product and 'add to cart' get shoved off-screen. People thumb-scroll once and leave.
Open your store on your own phone. Can you see what you sell and how to buy it without scrolling past a wall of marketing? If not, that's your first fix.
Slow load murders mobile sales
Phones on mobile data are less forgiving than a desktop on office wifi. Every app script, oversized image and auto-playing video adds seconds, and seconds are conversions. Mobile is where a bloated theme shows its true cost.
Test your store on a phone on mobile data, not wifi. If it crawls, that's a big part of the gap, and it usually traces back to too many apps and unoptimised images.
Fiddly taps and forms
Buttons too small or too close together, form fields that don't bring up the right keyboard, a checkout that demands typing an address by thumb, every bit of friction costs more on mobile than desktop. What's a minor annoyance with a mouse is a dealbreaker with a thumb on a train.
Wallets like Apple Pay and Shop Pay exist precisely to skip the typing. Making sure they're on and prominent is one of the highest-leverage mobile fixes there is.
The 60-second buy test
Here's the whole diagnosis in one exercise: pick up your phone, go to your store on mobile data, and try to buy something in under a minute. Every place you pause, squint, mis-tap or wait is a place real customers are giving up.
Fix the worst one you hit, re-check your mobile conversion rate a couple of weeks later, then do the next. You don't need a redesign, you need to remove the friction one honest test keeps surfacing.
More on turning traffic into sales: Getting traffic but no sales on Shopify? Here's where it leaks. · Shopify: lots of add to carts, no checkouts · How discount codes train Shopify shoppers to abandon their carts.