Design the phone held one-handed, not the desktop you built on.
Most templates are designed on a wide monitor and judged on a phone, held in one hand, on a couch. That gap is where polish quietly leaks.
The tells I look for first on mobile: the primary CTA parked top-right where a thumb cannot reach, a hero that needs two scrolls before it says what the product even is, and tap targets packed so tight that the wrong link fires.
Build the one-handed version first. Primary action in the bottom third where the thumb actually lives, the hero earning its meaning inside the first screen, 44px-plus tap targets with real spacing around them. The desktop almost always takes care of itself after that.
What is the first thing you check on a template's mobile view?
