What store screenshots are actually for
App store screenshots are the primary conversion surface for a listing, and most users see only the first two before deciding whether to scroll. That makes the first image a headline rather than a demonstration: it should communicate the single most valuable thing the app does, in words large enough to read in a search results thumbnail.
A raw screenshot of the interface, unframed and uncaptioned, performs poorly for this reason. Interface text is far too small to read at thumbnail scale, and a screen without context does not explain a benefit. The convention that works is a short caption in large type above or below a device frame, with the screenshot inside it as supporting evidence.
A sequence should tell a story rather than tour the menu structure. Lead with the core value, follow with the two or three features that differentiate, and keep any onboarding or settings screens out entirely — nobody installs an app because its preferences panel is well organised.
Sizes and store requirements
Both stores are specific, and a listing can be rejected or simply look wrong if the sizes are off. Apple requires screenshots matching current device resolutions, with 6.9-inch and 6.5-inch iPhone sizes being the ones most listings must supply, plus 12.9-inch or 13-inch iPad sizes if the app supports iPad. Uploading the largest required size often lets smaller ones be derived, but the framing is then not optimised for each.
Google Play is more permissive: between 2 and 8 phone screenshots, each with a minimum dimension of 320 pixels and a maximum of 3,840, with a 16:9 or 9:16 aspect ratio recommended. Play also requires a separate feature graphic at 1024 × 500, which is a distinct asset and frequently forgotten.
Both stores reject screenshots that misrepresent the app, which includes showing interface elements that do not exist, using device frames from a platform you are not listing on, and including pricing or promotional claims in the images. Apple additionally rejects screenshots showing a device frame other than an Apple one.
Making the images honest and legible
Use realistic content rather than placeholder data. Screenshots full of "Lorem ipsum" or obviously fake names read as unfinished, and stores increasingly treat clearly fabricated content as misrepresentation. Populate the app with plausible data and capture that.
Localise if you list in multiple languages. A screenshot with English captions on a Spanish listing measurably reduces conversion, and both stores support per-locale screenshot sets. The captions are usually the only part needing translation, which makes this cheaper than it sounds.
Check legibility at the size users actually see. Reduce your finished screenshot to roughly 100 pixels wide and look at it: if the caption is unreadable, the type is too small, which is the most common flaw in store listings. Also verify that important content is not hidden behind a device frame's notch or rounded corners, and strip any personal data from the captured screens before publishing.