Intro + Examples Human Interface Principles Platform Characteristics UX Guidelines This presentation has been developed in the context of the Mobile Applications Development course, DISIM, University of L'Aquila (Italy), Spring 2014. http://www.ivanomalavolta.com

1. Gran Sasso Science Institute
Ivano Malavolta
UI design

2. Roadmap
Intro + Examples
Human Interface Principles
Platform Characteristics
UX Guidelines

3. Introduction
Before focussing on UI….
in mobile you can always control
Content
naming
Visual
design

4. Content Naming
Before you start reasoning on the UI…
Define an APP DICTIONARY
Write down the terms and messages used in the app
ex.
– “tweets” in Twitter
– “likes” in Facebook

5. Visual Design
The direct representation of everything under your app
The first impression the user will have
It is not only about layout & colors…
it is about SENSORY SENSATIONS

6. Example 1
http://drbl.in/czjd

7. Anti-example 1

8. Roadmap
Intro + Examples
Human Interface Principles
Platform Characteristics
UX Guidelines

9. Aesthetic Integrity
It’s a measure of how well the appearance of the app
integrates with its function
• Productive app à order & clarity
• Game à gamish, frivoulous
• …

10. Consistency
Take advantage of the standards and paradigms people are
comfortable with
Does it use system-provided controls, views, and icons correctly?
Is the application consistent within itself?
Does text use uniform terminology and style?
Can people predict what will happen?

11. Direct Manipulation
Try to let your users direct manipulate objects in your app
Users can experience direct manipulation when they:
• Rotate or otherwise move the device
to affect onscreen objects
• Use gestures to manipulate
onscreen objects
• Can see that their actions have
immediate, visible results

12. Feedback
Acknowledge people’s actions and assures them that
processing is occurring
Users expect
• immediate feedback
• status updates during
lengthy operations

13. Metaphors
You may use metaphors for objects in the real world in your
app
Users will quickly grasp how to use the app
Ex.
– folders
– photo sliders
– …

14. User Control
People, not apps, should initiate and control actions
Apps can suggest actions, but users must do them
Apps can only infer data from the context
Users expect to be able to stop an operation that’s underway

15. Example 2
http://www.perspecdev.com/Faster/

16. Anti-example 2

17. Roadmap
Intro + Examples
Human Interface Principles
Platform Characteristics
UX Guidelines

18. Display is Paramount
The DISPLAY is (usually) the only means that users use to
interact with your app!
• The comfortable minimum size of tappable UI elements is
44 x 44 points
• The quality of app artwork is fundamental
• The user’s focus is on the content

19. Display Orientation
Users can rotate the device at any time and for any reason
Users tend to expect apps to launch in the device orientation
they’re currently using
TIP. You can use the splashscreen image to let the user rotate the
device

20. Gestures
Users don’t click, they use gestures
– tap/double tap
– drag
– zoom/pinch
– swipe
– flick
Users expect all these gestures to work the same,
regardless of the app they’re currently running

21. User Help
Keep onscreen user help as minimal as possible
In general, users don’t need onscreen help content to tell
them how to use the device or the apps
Remember of the Consistency human-interface principle

22. Example 3
http://j-a-m.co/balllin

23. Anti-example 3

24. Roadmap
Intro + Examples
Human Interface Principles
Platform Characteristics
UX Guidelines

25. Layout
It is the first aspect to fix
à you need pure feedback on it
à lo-fi wireframing
http://bit.ly/GTp82Q
Tablets
content scrolled
horizontally

26. Colors psychology
Users react to different colors differently
Colors evoke emotions
BLU
productiveness, interiors,
skies, peace, unity, harmony,
tranquility, calmness, trust,
coolness, confidence,
conservatism, water, ice,
loyalty, dependability,
cleanliness, technology…

27. Color Palette
Predefined number of colors to use consistently in your app
You can use tools like
palette choosers, or
palette pickers from images
OR
You can define your palette manually through the color
wheel
http://kuler.adobe.com

28. Color Wheel
Complementary
when you want something to stand out
Analogous
choose one color to dominate,
a second to support,
the third color is as an accent
http://bit.ly/GTv7on

29. Color Wheel
Triad
let one color dominate
and use the two others for accent
Square
works best if you let one color be
dominant
http://bit.ly/GTv7on

30. Typography
It is about:
• selection of the correct font
• understanding sizes
• applying conventional design methodologies
(size, shape, contrast, color, position, space, etc.)
http://bit.ly/GTvuzj

31. Readability guidelines
1. Use a high-contrast typeface
– Devices are usually used outdoor
2. Use the right typeface (font)
http://bit.ly/GTwUtv

32. Readability guidelines
3. Provide decent leading
– Leading = the space between two lines
4. Leave space on the right and left of each line
5. don’t crowd the screen

33. Readability guidelines
6. Generously utilize headings
– Divide the content into paragraphs
7. Use short paragraphs
– 2-3 sentences at most

34. Respect User-Entered data
Input is hard,
users slip (and sleep!)
Do whatever it takes to
preserve user data
and plan for real-world behaviors

35. Realize That Mobiles Are Personal
one device for one person
Don’t continuously ask for name, data, etc.
Only implement passwords and clear personal information
when required

36. Ensure That Lives Take Precedence
Don’t interrupt people’s life!
Differently from desktops
mobiles are glanced at, used in gaps between conversation
and driving and watching TV

37. Use Your Sensors
Whenever possible, perform actions for the user based on
sensors and user data
Ex.
Why should you have to silence your phone for a meeting,
when the phone knows where you physically are and knows
from your calendar that you have a meeting in that room right
now?

38. Focus on the Primary Task
you need to determine what’s most important in each
context or screen and…
focus on it exclusively!
Your app definition statement will help you focus on its
primary task

39. Give your users what they need most!
For example, in a game, people care about the experience,
they don’t expect to manage, consume, or create content
• Minimize the number of controls in the UI
• Customize controls so that they integrate with your
app’s graphical style
• Fade controls away after people have stopped
interacting with them for a little while
Elevate the Content that People Care About

40. Think Top Down
Put the most frequently used information near the top
Because users hold the device in the following ways:
• In the left hand and gesturing with a
finger of the right hand
• In one hand, and gesturing with the
thumb of the same hand
• Between their hands, and gesturing
with both thumbs

41. Logical Path
Make the path through the information you present logical
and easy to predict
– put markers to let them where they are
– put a back-button
Give users only one path to a screen

42. Easy Usage
Your app must be instantly understandable by users
à you cannot assume they want or they have time to learn how
to use your app
Make the main function of your app
immediately evident

43. User-Centric Terminology
use terminology your users understand
avoid technical jargon
– This does not hold if your target user is a technical guy

44. Inputting information takes time and attention, minimize it
TIP. If your app asks users a lot of input data, you have to revise
your design!
Balance any request for input by users with what you offer
them in return
Get information from the OS, when appropriate
– for example: contacts, address, events in the calendar…
Minimize the Effort Required for User Input

45. Enable Collaboration
Push for collaboration and sharing with others
When appropriate, make it easy for users to interact with others
– allow them to share things like their location, opinions, and
high scores
For tablets: think of ways to allow more than one person to use
your app on the same device

46. Brand Appropriately
Incorporate a brand’s colors or images in a refined, unobtrusive
way
Avoid taking space away from the content people care about
– Alternative: subtly customize the background of a screen

47. Make Search Quick
In apps with a lot of data, SEARCH can be a primary function
Build indexes of your data so that you are always prepared for
search
Live-filter local data so that you can display results more quickly
Display a search bar above a list or the index in a list
Display placeholder content right away and partial results as
they become available

48. Be Succinct
Think like a newspaper editor, and strive to convey information
in a condensed, headline style
When your UI text is short and direct, users can absorb it
quickly and easily
Give controls short labels, or use well-understood symbols
users should tell what they do at a glance

49. Use UI Elements Consistently
Follow the recommended usages for standard user interface
elements
à you can build on users’ prior experience
Avoid radically changing the appearance of a control that
performs a standard action
Never use the standard buttons and icons to mean something
else

50. Make Targets Fingertip-Size
Display may change, but the average size of a fingertip does not!
Give tappable elements in your application a target area of about
44 x 44 points
If you create smaller controls, the app becomes much less enjoyable
à
or people may focus on the interface only, rather that
content

51. People should have confidence that their work is always
preserved unless they explicitly cancel or delete it
Never ask for saving data, it should be done automatically
– You can ask to either edit or delete data
Ask People to Save Only When Necessary

52. Make Modal Tasks Occasional
Modality prevents users’ freedom by interrupting their workflow
and forcing them to choose a particular path
Keep modal tasks fairly short and narrowly focused
Always provide an obvious and safe way to exit a modal task

53. Start Instantly
Avoid displaying an About window or a splash screen
Avoid asking people to supply setup information
Delay a login requirement for long as possible:
– Focus your solution on the needs of 80 percent of your
users
– Get as much information as possible from other sources
– If you must ask for setup information, put it in your app’s
settings

54. Always Be Prepared to Stop
Save user data as often as reasonable
Save the current state when stopping

55. Example 4
http://instagr.am/

56. Anti-example 4

57. A Final BAD example
http://www.androiduipatterns.com/2011/11/cautionary-example-of-bad-design.html
Layout & icons

58. A Final BAD example
Navigation buttons
http://www.androiduipatterns.com/2011/11/cautionary-example-of-bad-design.html

59. A Final BAD example
Error Handling
http://www.androiduipatterns.com/2011/11/cautionary-example-of-bad-design.html

60. A Final BAD example
Data Handling
http://www.androiduipatterns.com/2011/11/cautionary-example-of-bad-design.html

61. References
Chapter 8
http://bit.ly/H4GnKZ
http://bit.ly/H4Gqq5

62. + 39 380 70 21 600
Contact
Ivano Malavolta |
Gran Sasso Science Institute
iivanoo
ivano.malavolta@univaq.it
www.ivanomalavolta.com