Using an iterative approach for app development The document outlines an iterative approach to developing personal tracking apps. It discusses: 1) Talking to people early to understand needs and exploring existing apps for ideas. 2) Sketching many alternative designs and prototyping top ideas to get early feedback. 3) Developing functional prototypes, collecting usage data and interviewing users to refine designs. 4) Releasing versions of successful apps, continuing to collect data and feedback to guide future improvements through an ongoing iterative process. The key benefits of this iterative process are identifying the right design early through testing, and obtaining rapid feedback to inform each cycle of refinement.

1. Using an iterative approach
for app development
Dr John Rooksby

2. I am researcher in Computing Science at Glasgow. I have
been studying how people use “personal tracking” apps

3. In this lecture
• I will give an overview of personal tracking
applications.
• I will give examples of applications I have worked
on at the University of Glasgow.
• I will outline the iterative development processes
taken to build these applications.
• I will emphasis the importance of sketching and
prototyping in early stage iterative development

4. Personal Tracking

5. Personal Tracking

6. Personal Tracking

13. Research issues
• Can these technologies help us make positive behaviour changes?
• When delivered through an app store?
• When recommended or prescribed by an expert?
• How do people use these technologies?
• Can we foster engagement and appropriate use?
• Can we present data in a meaningful way?
• Are there alternative uses of these apps that we hadn’t though
of?

14. Personal Tracking Applications Developed at the
University of Glasgow

15. Quped
• A Pedometer app
• Counts steps, sets goals
and allows you to compare
your steps with others.
• We want to know if it is
possible to recognise
behaviour changes “in the
wild”
• Released on Apple App Store

16. MatchFIT
• An information ‘hub’ that
presents step count and
standing time from a hardware
device, and supports
communication with peers.
• Application given to people
participating in a healthy
lifestyle programme. We want to
know if this application is
valuable after the lifestyle
programme completes.
• Multi-platform application
(Android, iOS, Web).

17. AppTracker
• Tracks what apps you use
and for how long
• This (arguably) was the first
app for personal tracking of
device use for iOS. We
wanted to explore how people
would use this kind of tracker.
• First released in 2013. New
version out now.

18. ScreenLife
• ScreenLife enables
you to track how
much time you spend
on mobile devices
and computers.
• Exploratory research
examining measures
of “screen time”
• Prototype evaluated
in 2015

19. How are these developed?

20. Iterative process

21. Boehm and Hansen (2000) Spiral Development: Experience, Principles and Refinements.

22. 1. Talk to people

23. Talk to people
• Try to do open,
exploratory interviews.
• Don’t just talk to
people like yourself.
• Be open to surprises

24. Look at what is already out there
• Look at apps.
• What do they
support?
• What do they do
well?
• What is missing?

26. 2. Sketch, and talk to people.

27. Sketch alternatives
• Quick sketches of as many alternative designs as
you can.
• Do this to force yourself to think creatively. Your
first idea is rarely your best.
• They don’t need to all be good ideas. Think
about bad ideas - what makes them bad?
• Talk to others about your ideas.

28. enerated by CamScanner from intsig.com
Generated by CamScanner from intsig.com
Generated by CamScanner from intsig.com
Generated by CamScanner from intsig.com Generated by CamScanner from intsig.com
Sketch alternatives
• Five sketches for a health and fitness app
• All of these were produced as “bad” or “wrong”
ideas for the particular project we were doing

29. Sketch alternatives
• Moving on to “serious” ideas

30. Refine sketches
• The step counts for each week are separate (left),
and then put together (right).

31. Producing a prototype

32. Formalising sketches
• These were produced using software called Sketch.

34. 3. Prototype, collect data, and talk to people.

35. Functional Prototype
• This was built this with
Apache Cordova
• It was not completely
finished, but “good enough”
to trial
• We ran a user trial with 12
people
• We logged interaction with
the app and interviewed
them after 2 weeks

36. Interviews
We interviewed (most of) the participants
• “Yeah it helped me compare myself against other people,
against a sort of a trend. So I could see if I was dramatically
below other people … so instead of getting the bus in the
morning I walked, but I didn’t like go out of my way to walk
more”.
• “You don’t know if these are sporty people, or if they walk a lot,
or err, this number here is not, it doesn’t represent much I think.”
• “I didn’t have much to write so I said hello. Maybe knowing the
other people would make me say more.”

37. Mon Dec 08 2014 21:39:59 GMT+0000 (GMT): app-start: "{}"
Mon Dec 08 2014 21:39:59 GMT+0000 (GMT): main-screen-data: "{"steps":6002,"you":7074,"friends":4433}"
Mon Dec 08 2014 21:40:04 GMT+0000 (GMT): main-swipe: {"page":1}
Mon Dec 08 2014 21:40:09 GMT+0000 (GMT): main-swipe: {"page":2}
Mon Dec 08 2014 21:40:16 GMT+0000 (GMT): main-swipe: {"page":1}
Mon Dec 08 2014 21:40:16 GMT+0000 (GMT): main-screen-data: "{"steps":6002,"you":7074,"friends":4433}"
Mon Dec 08 2014 21:40:18 GMT+0000 (GMT): main-swipe: {"page":2}
Mon Dec 08 2014 21:40:21 GMT+0000 (GMT): main-swipe: {"page":1}
Mon Dec 08 2014 21:40:21 GMT+0000 (GMT): main-screen-data: "{"steps":6002,"you":7074,"friends":4433}"
Mon Dec 08 2014 21:40:22 GMT+0000 (GMT): main-swipe: {"page":2}
Mon Dec 08 2014 21:40:23 GMT+0000 (GMT): open-post-comment: "{}"
Mon Dec 08 2014 21:40:28 GMT+0000 (GMT): main-swipe: {"page":1}
Mon Dec 08 2014 21:40:28 GMT+0000 (GMT): main-screen-data: "{"steps":6002,"you":7074,"friends":4433}"

38. Logs and Interviews
• Logs are good at showing what people did.
• Interviews are good for finding out why people did these things.
• For example:
• The logs showed us not many people wrote comments in the
app, the interviews helped us identify why.
• The logs showed us some people liked the daily steps view, but
others looked more at the weekly view, and in the interviews we
could address why.
• A trial gives you insights into how to improve an app, but its back to
the sketch book.

39. Full prototype
• Our next major
prototype was multi-
platform and
integrated with the
hardware tracker.
• Trialled with a
‘target group’ of
users over several
weeks.
• We collected log
data and
interviewed the
users after the trial.

41. 4. Release, collect data, and talk to people.

42. Release version
• Released and used
by ~350 people.
• It took multiple
design iterations to
get here.

43. Release version
• Analysis of release version mainly via log data.
• Indirect feedback via the sites.

44. Second release
• Now only collecting
quantitative data.
• Further redesigns
planned.
• Apps are never
finished!

46. Conclusion

47. Refined sketches
sketches
More sketches
Paper prototype
Functional prototype
Full prototype
Release
Iterative design looks somewhat like this
Further releases

48. • The hardest part of application development is not
implementation, but getting the design right.
• Implementation does take time
• So try not to implement the wrong thing!
• Iterative development allows you to:
• Make your mistakes as early as possible
• Helps you/customers articulate ideas
Why do iterative design?

49. • The key part of iterative development is getting feedback
• Qualitative feedback by talking to people
• Quantitative feedback through log data
• To get rapid feedback you can
• Create and discuss sketches
• Create and discuss ‘minimal’ prototypes
• Data becomes more valuable later on
What is iterative development?

50. Thank you.