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UX Planet — Medium | Ksenia Sternina
If you’ve ever had to move your iPad from one hand to the other just to tap a button you couldn’t reach, then you may have already guessed why we began this study in our UX lab.
Our Mail.Ru Group’s UX lab team carries out many usability studies of our apps for smartphones and tablets. We address users’ needs by introducing features in our products. We carefully test all of the functions to ensure users notice and understand them well. Nevertheless, this was the first time we had looked at the physiological aspect of our app’s usage.
We came across several studies dedicated to the physiology of using iPads, but they were all scientific, rather than practical, and quite far from business needs. Moreover, such studies were performed on smartphones alone, excluding tablets.
So, we decided to analyze the physiology of using the interface of Mail.Ru’s Email app; for example, how comfortable is it to use an iPad app in typical positions? The behaviors we studied included tapping buttons while lying down, browsing photos while sitting, swiping, and writing text. Our results revealed a number of purely ergonomic problems that should be taken into account when developing any iPad app.
Our results are shown here on an iPad layout using a three-color schema. Controls located in the green zone are easily reachable by the average person; the yellow zone is still reachable but not as easily; and the red zone is the most inconvenient location for controls.
Safe zones on iPad
First time was published here.
In terms of user experience, an iPad is interesting as a replacement for a notebook at home (when the user is lying on a couch) or on journeys (when the user is sitting on an airplane or in a hotel room). Such conditions differ greatly from the environment in which we first tested iPad apps. The majority of our previous studies were carried out in a laboratory with an iPad fixed to a bench and using an eye-tracking device. However, we soon learned that this wasn’t suitable for our study because we needed to observe how people use iPads in their everyday environment. So, instead, we had our respondents sit or lie down on a couch to simulate natural conditions.
Tobii mobile eye-tracker in our UX lab
Our audience consisted of the following:
All respondents use an iPad, in particular, to check their Mail.Ru email.
Every user would lie or sit on a couch in the pose that is the most natural for them when using their iPad:
This study dealt only with usage in landscape orientation because a number of studies show the majority of iPad users prefer it. Some research shows that it accounts for 35% of usage and is used mostly for specific passive tasks that don’t involve tapping buttons, such as reading a book.
Respondents in different positions when using an iPad
Users performed their usual actions with the email app in scenarios such as the following:
User interface of email app
All activities were recorded with a GoPro camer (worn by the respondents) and an external camera.
Respondents with GoPro camera
Analysis of the video showed that some difficulties in using iPad apps were purely physiological — for example, a user seeing all buttons and understanding which one to push and when, but not being able to do so comfortably.
We discovered the following difficulties:
Examples of each difficulty are listed below.
Extra features in an app are often available via swiping. For instance, users of Mail.Ru’s Email app swipe to interact with the message list. Respondents mentioned that the outer buttons (“Spam” and “Trash”) were positioned too far away. This particularly affected those sitting on a couch. As they held the iPad with their left hand, keeping hold of it to reach those buttons proved to be uncomfortable, and so they had to stretch their thumb to reach.
Respondents had to stretch their thumb to reach buttons
Respondents sometimes had to change their finger position when performing a step-by-step operation. For instance, the first two steps for adding a second account to the email app is performed in the center of the screen, but the button for the third step is at the bottom of the screen. To press it, respondents had to change their finger position.
To proceed with the registration process, users had to change their finger position three times
Sometimes, our respondents changed hands while performing step-by-step operations; for example, when using the app’s menu. Seven out of eight respondents browsed the menu with their left thumb. All of them found it easy to tap the menu options, but they found it difficult to empty the “Trash” folder. That button was too far away to be easily reached (note that four out of eight respondents had to do it with their right hand instead of their left, which was normally used to access the menu). Moreover, this task required two steps: emptying the folder and then confirming the operation. The second step was difficult for respondents who managed to tap the “Trash” folder with their left thumb, because the second step had to be performed with the right hand.
To clear the “Trash” folder, users had to change hands
Due to the size and shape of the device, some areas of the screen were difficult to tap. A hand would be pressed against the iPad and have to be bent unnaturally to tap a button.
Let’s take the location of the “Save Image” button as an example. The respondents sitting on the couch found it difficult to tap this button. The icon is located in the upper part of the screen, at the edge of the viewport. Therefore, using the index or middle finger, as is usually done, wasn’t quite comfortable because the metacarpophalangeal joint of the thumb was pressed against the device.
When pushing the “Save Image” button, the metacarpophalangeal joint of the thumb pressed against the device
Buttons in apps are traditionally located in the upper part of the screen, following the common practice on websites. But this location has turned out to be inconvenient, both for smartphones and tablets. When tapping a button in the upper part of the screen, the hand will end up covering most of the screen. Also, the part of the screen where changes caused by tapping certain buttons appear is also covered. This will sometimes confuse the user, who might need a couple of seconds to understand what has occurred as a result of their selection.
I can illustrate this point using our email app’s “Compose” button. One of the respondents used their left hand to tap it. Reaching the center of the screen this way isn’t very comfortable but still possible.
When pressing the “Write a letter” button, the active hand covers half the screen
However, the other seven respondents used their right hand, covering more than half of the screen:
When the right hand is used to press the “Write a letter” button, over half the screen is covered
An iPad’s physiology-friendly zones for various body positions are shown below. The calculation was performed based on the average length of a finger (the average length being 5.8 cm for males and 5.3 cm for females for 95% of the US population). According to research, male and female iPad users are essentially equally represented (as of June 2012, males accounted for 51.9% of all iPad users, but we’ll consider usage to be equal for the sake of convenience). Therefore, we’ve used the average length for both male and female fingers. And because all of our respondents, as well as most (85%) people in general, are right-handed, these safe zones were determined for right-handed people. For left-handed users, the safe zones would need to be inverted.
The results below take into account the dimensions of an iPad’s frame, being 2 × 1 cm.
Because our respondents used controls located in various parts of the screen, the safe zones we determined could be applied to any iPad app.
Refer to the layout below for physiology-friendly locations of iPad app controls. The diagram applies to a user sitting on a couch with an iPad on their knees.
The controls in the green zone are the easiest to reach for the average person. The yellow zone is still reachable but not as easily. The red zone is the most inconvenient location for controls; a user will encounter several of the difficulties mentioned above; for example, they would have to move their hand to tap a button and end up covering most of the screen.
Safe zones on iPad when user is seated
This safe zone layout applies to a user lying supine; in other words, lying down, face up, with the iPad resting on their stomach and being held with both hands. Note that the red zone in the lower part of the screen is larger than in all other layouts. An iPad supported by your abdomen in this way over an extended period of time will create a ridge in one’s clothes. This ridge would be about 1 to 2 centimeters high and would cover the controls in the lower part of the screen.
Clothes cover part of the screen for users lying on a couch
The third layout applies to a user lying prone; that is to say, lying face down on the couch. In this position, the person has to rest on their forearms, which significantly limits the mobility of their hands, making use of both thumbs the most comfortable way to navigate.
However, because the left hand of right-handed users is holding the device, there are more green zones for the right hand.
Safe zones on iPad when user is lying prone on the couch
The illustration below combines all of the zones for the different body positions into one layout. The areas where green and yellow zones overlap are shown in yellow, while the ones where the green and red zones overlap are shown in red. This enabled us to develop the layout of absolutely safe green zones for all of the body positions of iPad users.
All of the layouts were developed according to the dimensions of the iPad’s bezel, which is 2 centimeters on the left and right sides and 1 centimeter on the upper and lower edges, assuming it is held horizontally. If your app is designed for iPad mini users, you should measure the edges of that device to determine your own safe zones.
Safe zones on the iPad for all positions
We hope the results of this study will assist all developers to improve the usability of their apps during the creation process. We are certain that the results of our study would be relevant to the design of any app, because it was in no way affected by the design of our own app. Respondents were familiar with all of the controls, and our findings were based solely on physiological observations. In addition, note that the Mail.Ru Email app has controls on every side of the screen, so we’re sure that the device’s entire surface was tested.
A user chooses the time when they want to receive push notifications
The user selects a message style
If, in a few months (and after having absorbed the recommendations derived from our research here), you find yourself having to change hands less often while using an iPad and you are able to hit controls and menu items more easily and frequently, then you’ll know we’ve addressed the problem effectively.
Email registration page in Mail.Ru Email app with safe zones
Message page with safe zones
App menu with safe zones
Settings window with safe zones
How To Make A Physiology-Friendly Application For The iPad was originally published in UX Planet on Medium, where people are continuing the conversation by highlighting and responding to this story.
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