http://fr.droidcon.com/2014/agenda/detail?title=+The+secret+to+building+cross+platform+Mobile+Apps%3A+How+the+big+guys+do+it Today's mobile ecosystem is silo-ed. It's often hard to build for each complex platform, which are each important in their own right, but if we take a step back, the value of going cross-platform is the seamless experience you can build for your customers across the many devices they use throughout the day. Learn how Ali Parr, head of Partner Engineering at Facebook & Parse, has been working with the most disruptive tech companies for the last couple of years, helping them build cross-platform Mobile Apps that scale to millions of users and becoming highly profitable businesses. Speaker: Ali Parr, Parse (Facebook Company) Head of Mobile Platform Partnerships Engineering, EMEA, Facebook and Parse, based in London. He currently heads up the Parse partnerships program for Facebook in EMEA, as well focusing on new developer acquisition. Ali is focused on building partnerships between Parse and developers across EMEA, through direct contact, public speaking opportunities, and mentoring events. Ali is also a mentor at Techstars in London, and The Family in Paris, providing advice and experience to high-potential startups. Prior to Facebook, Ali was the founder of Infinite Degree, a gaming startup that reached top 10 in Apple App Store across many regions including the US and the UK. Ali holds a Masters degree in Computer Science.

1. ACCELERATING GROWTH BY DEVELOPING
CROSS PLATFORM
ALI PARR
PLATFORM PARTNERSHIPS, FACEBOOK, EMEA

4. 1903
First Flight

5. 1903
First Flight
1928
Jet Power

6. 1903
First Flight
1928
Jet Power
1947
Aeroflot

7. 1903
First Flight
1928
Jet Power
1947
Aeroflot
1969
Moon!

8. 1903
First Flight
1928
Jet Power
1947
Aeroflot
1969
Moon!
1973
Concorde

9. 1903
First Flight
25 years 19 years 15 years 7 years
1928
Jet Power
1947
Aeroflot
1969
Moon!
1973
Concorde

10. 1903
First Flight
1928
Jet Power
1947
Aeroflot
1969
Moon!
1973
Concorde

11. 1903
First Flight
1928
Jet Power
1947
Aeroflot
1969
Moon!
1973
Concorde

12. 1903
First Flight
1928
Jet Power
1947
Aeroflot
1969
Moon!
1973
Concorde
1960s
ARPANET

13. 1903
First Flight
1928
Jet Power
1947
Aeroflot
1969
Moon!
1973
Concorde
1960s
ARPANET
1993
Mosaic (Netscape)

14. 1903
First Flight
1928
Jet Power
1947
Aeroflot
1969
Moon!
1973
Concorde
1960s
ARPANET
1993
Mosaic (Netscape)
1999
.com Boom

15. 1903
First Flight
1928
Jet Power
1947
Aeroflot
1969
Moon!
1973
Concorde
1960s
ARPANET
1993
Mosaic (Netscape)
1999
.com Boom
2007 - 2008
iPhone / Android

16. 1903
First Flight
1928
Jet Power
1947
Aeroflot
1969
Moon!
1973
Concorde
1960s
ARPANET
1993
Mosaic (Netscape)
1999
.com Boom
2007 - 2008
iPhone / Android
2010 >
Cloud

21. 1. AS A TECHNOLOGY MATURES,
SPEED INCREASINGLY MATTERS

23. $ git-clone-www ~/www

24. 14000
11200
8400
5600
2800
0
COMMITS / ENGINEERS PER MONTH
2007 2008 2009 2010 2011 2012 2013

29. 2. SUCCESSFUL PROJECTS SCALE

30. A STORY…

31. 70
56
42
28
14
0
CANDY CRUSH CANVAS MAU
Q1-12 Q2-12 Q3-12
Q4-12

32. 70
56
42
28
14
0
CANDY CRUSH CANVAS MAU (EXPECTED)
Q1-12 Q2-12 Q3-12 Q1-13
Q4-12

33. 500
400
300
200
100
0
CANDY CRUSH MAU (ACTUAL)
Q1-12 Q2-12 Q3-12 Q1-13 Q2-13 Q3-13 Q4-13
Q4-12

34. THE WORLD WENT MOBILE

35. 2005

36. 2013

39. THE ENGAGEMENT LOOP

40. ‘THE LOOP’ IN CANDY CRUSH
• Progress synced across platforms - Levels, scores etc
• ‘Lives’ mechanic - false scarcity
• Friends and progress (via Facebook) - competition
• Sharing and stories - exposure
• Regular, small gameplay sessions builds loyalty (*cough* addiction)

41. About 0.15% of mobile gamers contribute.. 50% of all of the in-app purchases
generated in free-to-play games.

42. About 0.15% of mobile gamers contribute.. 50% of all of the in-app purchases
generated in free-to-play games.
Keeping these users engaged is vital!

44. IT’S NOT JUST TRUE FOR GAMING….

45. 3. CROSS-PLATFORM ROCKS

47. FACEBOOK MOBILE USAGE

48. iOS Android Mobile Web
1.07b MAP
FACEBOOK MOBILE USAGE

49. 2009

55. “Why has the Facebook app been so slow? Because the current version of the
app is nothing more than a web browser inside an Objective-C shell. Stuff is
being constantly pulled from the web, hence the lag time.
The next Facebook app will replace all that sluggish sludge by using more
Objective-C, which in turn would use more of the iPhone's hardware so it has to
collect less information from the Web."
- Gizmodo, May 2011

56. “Our biggest mistake was betting too much on HTML5."
- Mark Zuckerberg, September 2012

59. ENGINEERING FIRST

60. PEOPLE FIRST

62. 4. CROSS-PLATFORM IS REALLY HARD

63. 1. SPEED MATTERS
2. SUCCESSFUL PROJECTS SCALE
3. CROSS-PLATFORM ROCKS
4. CROSS-PLATFORM IS REALLY HARD

66. ALWAYS BE SHIPPING

69. Developer Workflow
Trunk www
(SVN)

70. Developer Workflow
Trunk www
(SVN)

71. Developer Workflow
Trunk www
(SVN)
Local Branch
(Mercurial)
Branch
from
Trunk

72. Developer Workflow
Trunk www
(SVN)
Local Branch
(Mercurial)
Branch
from
Trunk
Locally commit your
changes as you go

73. Developer Workflow
Trunk www
(SVN)
Local Branch
(Mercurial)
Rebase
regularly
Branch
from
Trunk
Locally commit your
changes as you go

74. Developer Workflow
Trunk www
(SVN)
Local Branch
(Mercurial)
Rebase
regularly
Branch
from
Trunk
Locally commit your
changes as you go
Tests!

75. Developer Workflow
Trunk www
(SVN)
Local Branch
(Mercurial)
Rebase
regularly
Branch
from
Trunk
Differential
Submit for
code review
Locally commit your
changes as you go
Tests!

76. Developer Workflow
Trunk www
(SVN)
Local Branch
(Mercurial)
Rebase
regularly
Branch
from
Trunk
Differential
Submit for
code review
Locally commit your
changes as you go
Reviewer says
yeah!
Tests!

77. Developer Workflow
Trunk www
(SVN)
Local Branch
(Mercurial)
Rebase
regularly
Branch
from
Trunk
Differential
Submit for
code review
Ready for
commit
Locally commit your
changes as you go
Reviewer says
yeah!
Tests!

78. Developer Workflow
Trunk www
(SVN)
Local Branch
(Mercurial)
Rebase
regularly
Branch
from
Trunk
Rebase
again
Differential
Submit for
code review
Ready for
commit
Locally commit your
changes as you go
Reviewer says
yeah!
Tests!

79. Developer Workflow
Trunk www
(SVN)
Local Branch
(Mercurial)
Rebase
regularly
Branch
from
Trunk
Commit
Rebase
again
Differential
Submit for
code review
Ready for
commit
Locally commit your
changes as you go
Reviewer says
yeah!
Tests!
Tests!

80. .org

82. SHIPPING CAN BE PAINFUL…

83. …BUT IT LEADS TO UNDERSTANDING

84. MEASURE:
TO LEARN ABOUT YOUR USERS

85. OKCUPID: LOVE IS BLIND

86. OKCUPID: LOVE IS BLIND

87. OKCUPID: LOVE IS BLIND

88. OKCUPID: LOVE IS BLIND

90. CREDIT CARD ENTRY EXPERIENCE
VERSION A VERSION B

91. CREDIT CARD ENTRY EXPERIENCE
VERSION A VERSION B
+2.4% lift in completions
People like their keyboards. They also like things that match
VERSION A

92. DEBIT CARDS AND CREDIT CARDS
VERSION A VERSION B
Credit Card Credit/Debit Card

93. DEBIT CARDS AND CREDIT CARDS
VERSION A VERSION B
Credit Card Credit/Debit Card
+1.5% lift in rate of credit cards added
Make options obvious, even if it seems obvious to you
VERSION B

94. MINIMIZING CANCEL BUTTONS
VERSION A VERSION B

95. MINIMIZING CANCEL BUTTONS
VERSION A VERSION B
Conversion up but refund rate increased by 30%
Bad experiences can raise conversion temporarily, but not permanently
MIX

96. COUPON FLOW EXPERIENCE
VERSION A VERSION B

97. COUPON FLOW EXPERIENCE
VERSION A VERSION B
+30% lift in payer rate
Don’t distract your customers from the main objective VERSION B

98. MEASURE:
ENSURE YOU MEASURE THE RIGHT THINGS

99. LET’S PLAY A GUESSING GAME
ARPPU
% of payers
C
B
A
D

100. WHICH ONE HAS THE “BEST” MONETIZATION?
ARPPU
% of payers
C
B
A
D

101. IT ALL BEGINS WITH ENGAGEMENT
ARPPU
% of payers
C

102. OUTSOURCE, OUTSOURCE, OUTSOURCE

105. 1. ALWAYS BE SHIPPING
2.MEASURE, ITERATE, IMPROVE
3. OUTSOURCE

106. THANKS, QUESTIONS?