Mobile vs desktop conversion rate is the first split you should make on any Shopify analytics number, because the blended figure you have been quoting is an average of two different stores. One store gets browsed on a couch with a thumb. The other gets bought from at a desk with a credit card already out. They share a URL and almost nothing else.
A blended conversion rate is like a blended body temperature for two patients. “Averaging 37 degrees” sounds healthy right up until you notice one of them is on fire. On most stores mobile brings the majority of sessions and converts at a fraction of desktop, which means the blended number is quietly dominated by your weakest experience while feeling reassuringly stable.
One store, split in two
Illustrative numbers. The blended rate is not a fact about your store, it is the average of two facts.
The blend looks fine. The split says your mobile experience converts at roughly a third of desktop, and mobile is where the traffic is. That is not a detail, that is the headline.
Make the split, then read it
In Shopify Analytics, open your sessions and conversion reports and break them down by device type; in GA4, add “device category” as a dimension to any funnel or conversion report. Ten minutes, and you now have two conversion rates, two AOVs, and a traffic share for each device. Write them next to the baseline you took in tip 1.
Some gap is structural and not your fault. People genuinely research on the phone and buy on the laptop later, and no sticky button will change that. But the size of the gap is yours. As a working rule: if mobile converts at less than half of desktop, you have a mobile problem, not a “customers prefer desktop” anthropology finding. Something in the phone experience, speed, layout, forms, reachability, is charging you a toll on the majority of your visitors.
The split also changes how you read every experiment for the rest of this series. A change that lifts mobile 10% and does nothing on desktop can drown in a blended number. From now on, every before-and-after you run gets judged per device. Blended numbers are for investor decks. Split numbers are for fixing things.
