Most of your install decision happens before anyone opens your product page. In App Store search results, your first screenshots appear right under the app name, and for many users that glance IS the evaluation. Changing a first screenshot alone has moved conversion by 15 to 30 percent in published tests. Here is how to treat slide one like the billboard it is.
Where the first screenshot actually appears
Three surfaces, in decreasing size: search results (two to three portrait screenshots visible without any tap), your product page above the fold, and various featuring cards. The search result surface is the brutal one: your screenshot competes directly against the two apps above and below you, at thumbnail size, for about a second of attention.
What belongs on slide one
One benefit, stated big. The user should be able to answer "what do I get?" from the thumbnail alone:
- The caption carries the message. A short, benefit-first line in large type. If it is not legible at thumbnail size, it does not exist. Formulas that work are covered in caption formulas that sell.
- The screenshot proves it. Your best screen, the one that shows the promise being kept. Real UI, by the way, is not optional: Apple's Guideline 2.3.3 requires it.
- Nothing else. No feature list, no five badges, no onboarding screen. One idea.
What does not belong there
Splash screens, logos on gradients, login pages, "welcome" screens. They say nothing, and they burn the most valuable pixel real estate you own. The same goes for your weakest screen shipped first because it happens to be the app's home view: lead with the strongest moment of the product, not the first chronological one.
The 70 percent rule
Across published listing tests, the first three frames carry roughly 70 percent of the conversion weight of the whole set. Practical consequence: spend your design and testing effort in proportion. Slides four to ten are for the convinced, slides one to three are for everyone. When you A/B test your screenshots, start with slide one; it is where variance actually moves installs.
Check it like a user
Export your set, shrink slide one to about 200 pixels wide, and look at it for one second. Can you read the caption? Do you know what the app does? If not, iterate: it costs minutes in a screenshot composer, and it is the highest-leverage design minute in your listing.
The short version
Slide one is a billboard seen at thumbnail size in search results. One benefit, huge caption, proof screenshot, nothing else, and test it first: it carries more conversion weight than the rest of the set combined.
