The Psychology of Swiping in Apps
Swiping is a primitive gesture. Babies as young as 17 days old have been observed making swiping motions at objects they find interesting. In the field of app design, which often seeks to harness primitive impulses, it only makes sense that swiping would emerge as a key means of navigation.
In the UX space, swiping is perhaps most readily associated with the dating app Tinder, which pioneered the use of this simple, yet addictive, gesture. Tinder users work their way through stacks of cards featuring an image of a potential date. They swipe right if they are interested and left if they are not. If both users swipe right on each other, they are “matched” and can then exchange messages. As of 2018, there were an estimated 50 million Tinder users. Attesting to the efficacy of swiping as a model, these users collectively swipe 1.6 billion times per day.
Apps that serve a wide variety of purposes have begun to adopt this utility to their specific needs, notably in the eCommerce sphere.
What is swiping?
Google’s Material Design System defines swiping as separate from other gestures such as flicking and scrolling. Per their manual, a swiping gesture allows users to “slide elements to complete actions upon passing a threshold.” It mimics the analog motion of swiping a card off of the top of a deck.
In practice, this is usually accomplished with one finger, often the thumb. Swiping is particularly amenable to the so-called “thumb zone” proposed by Steven Hoober in his 2011 book Designing Mobile Interfaces. Hoober found that nearly 50% of mobile phone users preferred to navigate using a single thumb. Thus, accessibility of app features to that finger is crucial; users prefer not to have to stretch their thumbs or readjust their grip in order to execute a function. The relatively crude movement of the swipe perfectly aligns with this tendency.
Why does swiping matter?
Because it is so intuitive and natural, the swiping motion has become a key factor to consider in UX design. Its left-right orientation also aligns with the way that we read and visualize time. Unlike other means of executing commands, like pressing a digital button or link, swiping is a much faster motion and quickly becomes almost subconscious. Particularly for apps that require quick browsing functionality, swiping can be key to retaining the user’s attention. If browsing becomes time-consuming or visually confusing, users are more likely to leave.
Apps like Tinder employ what is called a variable reward schedule, much like a slot machine at a casino. Each rejected card in the stack builds anticipation in the user, who expects that eventually, something good will come along — say, a prospective date. This process harnesses the brain’s reward pathway, releasing dopamine. This same chemical is released by a wide range of activities, including eating and using drugs. Intriguingly, dopamine is also released by the anticipation of the reward, often at higher levels than are released by the consumption of the reward itself. As one might expect from a neurotransmitter that is released upon the ingestion of drugs, dopamine is a key factor in forming addiction pathways and is responsible for the addictive nature of some digital activities.
In a fascinating twist, even “negative” actions, such as swiping left on a potential date or rejecting an item of clothing, elicit positive responses in users. Users typically prefer to reject one of two less-than-ideal choices rather than accept one of them. This can contribute to a feeling of empowerment in the user. App designers can harness this tendency.
Users are often overwhelmed by a surfeit of choice, especially when it comes to eCommerce. The tendency to abandon a shopping session is often attributed to choice paralysis — the inability to make a decision in the face of too many options and too much information. Presenting merchandise in a manner that allows them to view items one at a time decreases the overwhelming nature of viewing multiple objects at once, as is the case with the grid format familiar to most online shoppers. Presenting each object discretely tends to increase browsing time. One possible explanation for this, particularly as it applies to fashion apps that allow users to browse clothing, is that swiping mimics the action of flipping through racks of garments in the real world.
The feedback provided by rejecting most items and selecting a few both personalizes and refines the experience for the shopper and allows app developers to collect valuable data about their customer base. One study demonstrated that shopping apps that use swiping technology allowed users to better retain information and encouraged return visits.
Is swiping right for your app?
With mobile use fast outpacing desktop use, swiping is increasingly viable in a range of apps. About 63% of website hits in 2017 originated from mobile devices rather than from desktop computers. This diminishes, but does not entirely eliminate, concerns about cross-platform utility. Swiping behaviors are simply less attractive to desktop users due to the nature of the interface: the swiping motion is less intuitive when paired with the vertical modality of a computer mouse. If your app is a hybrid app intended for both mobile and desktop use, make sure that no essential information is obscured by a horizontal scrollbar, which makes users less likely to continue browsing.
Within the space of mobile eCommerce, swiping is most effective to employ when displaying items that have visual appeal. If your app sells auto parts or household supplies, users are unlikely to enjoy swiping through images of similar and uninteresting items. However, if you’re selling something like designer clothing or furniture, the swiping process is likely to be much more enjoyable to the user and can expose them to a wider range of your products than they may have otherwise explored. The range of products can also determine whether or not swiping gestures are effective at engaging customers. If your shopping platform only offers a limited number of items, swiping will probably be less useful to users.
Apps that are meant to be used in tandem with other activities, such as cooking, are also great platforms to implement swiping. Because the user’s attention will be divided, a simple motion like swiping is much easier to perform than attempting to scroll or click on a button.
If you ultimately decide to introduce a swiping function to your app, make sure that the intent of a swipe is immediately clear to the user. Does swiping delete an item from a list? Does it move an item to a cart or wish list? Swiping should be used to perform one discrete function. If swiping can both delete an item in one context and save it in another, users are likely to get confused and even become dissatisfied with your app. However, when implemented right, swiping can increase engagement and enable your app to provide a better, smoother user experience.
