Slide to unlock
DocumentedWhen Steve Jobs introduced the iPhone in January 2007, the first gesture he demonstrated was sliding a finger across the screen to unlock it. The control was a track with an arrow-shaped knob and the words “slide to unlock” shimmering along it.
Our readingIt solved two problems at once: it prevented pocket unlocks, and it taught a whole population that glass could be dragged. In Don Norman's language, the knob and shimmering text were signifiers, cues that announce what action is possible. The gesture taught itself.
Pull to refresh
DocumentedDeveloper Loren Brichter introduced pull-to-refresh in Tweetie, his Twitter app for the iPhone, around 2008–2009. Drag the top of a list down, feel it resist, let go, and new posts load. Twitter later acquired Tweetie, and the pattern spread to almost every feed-based app.
Our readingIt borrows the physics of a spring. You are already scrolled to the top, your thumb wants to keep going, and the interface turns that leftover motion into a request. Brichter has since said he has mixed feelings about how compulsive it can become.
Undo Send
DocumentedGmail first offered Undo Send as an experimental Labs feature in 2009 and made it a standard setting in 2015. The message is not recalled from the recipient; Gmail simply waits a few seconds (up to 30, configurable) before actually sending it.
Our readingThis is our favourite kind of clever: honest. The interface admits a delay exists and gives it a purpose. It also embodies two of Jakob Nielsen's 1994 usability heuristics, “visibility of system status” and “user control and freedom”, in one small link.
Infinite scroll
DocumentedAza Raskin is widely credited with designing infinite scroll around 2006: content that loads continuously as you approach the bottom, with no “next page” button. He has since spoken publicly about regretting how it is used to hold attention.
Our readingRemoving a button removed a pause. A “next page” link is a tiny moment of choice; without it, stopping becomes your job. It also makes footers, and the legal links inside them, notoriously hard to reach.
The rules underneath
Clever interfaces lean on principles that are older than the web:
Fitts's law (1954)
Psychologist Paul Fitts showed that the time to reach a target depends on its distance and size. Big, close buttons are faster; screen corners and edges are easy to hit.
Affordances and signifiers
Don Norman's The Design of Everyday Things (1988, revised 2013) explains why a door handle tells you to pull, and why a flat label rarely tells you to press.
WCAG 2.2 target size
The W3C's Web Content Accessibility Guidelines 2.2 (2023) include success criterion 2.5.8, which asks for pointer targets of at least 24 by 24 CSS pixels, or enough spacing around smaller ones.
Deceptive patterns
In 2010 designer Harry Brignull coined “dark patterns” for interfaces that trick people: pre-ticked boxes, hidden cancel buttons, guilt-laden “No thanks” links. His catalogue now lives at deceptive.design.
Caveat: credit is often shared
Interface patterns rarely have a single inventor. We name the people most widely credited, based on their own accounts and contemporary reporting, while recognising that similar ideas often appeared in parallel elsewhere.