While the iOS App Store search interface has changed over time, and continues to change, Apple has used other designs in its “Search” interface to ensure oversized portions of the user interface lead users away from competitors’ apps and towards Apple-curated lists or Apple-selected advertisements.
Moreover, Apple’s “Stories” for categories such as email act as a further barrier to entry and innovation. The iOS App Store interface is designed to draw users to the “Story” before they might encounter a list of other applications.
In that “Story,” Apple offers only a limited number of email applications that Apple selects – a list that has remained essentially static for nearly 2 years – presenting a significant barrier to entry by new email applications.
“Story” 
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