Cross-platform mobile app development faces many challenges including differences in programming languages, features, monetization options, and user interface paradigms across platforms. Native development for each platform offers the best integration and reach but requires the most effort. Cross-platform tools provide easier multi-platform development but with limitations in native features and user experience consistency. Choosing the right strategy depends on an app's goals, target platforms and audiences, and a developer's technical skills and resources. While cross-platform tools improve, fully native apps still have advantages for high-quality experiences.

1. Grenzen der
Crossplattform-Entwicklung
Robert Virkus
@robert_virkus
14:15 (naja, so ungefähr) - 15:15

2. Enough Software
A Team of Mobile Enthusiasts
Headquarter: Bremen, Germany
Customer base: worldwide

3. 2005
-3 M
Stone age
-4,600 M -3,500 M -2,000 M -225 until -65 M
Earth forms Life forms Complex life forms Age of dinosaurs

6. Our products
Open Source Tools for App Developers
J2ME Polish
The standard framework for Rich UI Library for Native BlackBerry UI
Java ME development Samsungs bada platform development made easy
Automatic porting to Native API extensions
Android and BlackBerry optimize app performance
More than 1 million
downloads

8. Non-Profit Project
Mobile Developer’s Guide
to the Galaxy
The popular, and free, handbook for developers
and decision makers
Community-driven, objective, and non-profit
45,000 hardcopies distributed,
over 100k in downloads
12th Edition out now
Download at enough.de/mdgg
Tweet about it #mdgg

9. The Difficulties of
Going cross-Platform
(c) Madlen Ehrlich

10. Mobile Platforms
J2ME

11. Mobile Platforms

12. Cross-Platform Challenges
1. Programming Languages
2. Features
3. In app purchase
4. In app advertisement
5. Push Notifications
6. Desktop Integration
7. UI & UX
8. OS Versions

13. Challenge:
Programming Languages
Objective-C
C/C++ 10
C#
Java
JavaScript

14. Challenge:
In-App Purchase

15. Challenge:
In-App Advertisement

16. Challenge:
Push Notifications
8192
7168
6144 Data size from 256 bytes to 8kb
5120 Different transport protocols
4096
Different options (direct text, data)
3072
Different desktop visualisations
2048
(badges, notifications)
1024
0
Max Push Size in Bytes
iOS Android
Windows Phone BlackBerry

17. Challenge:
Features
J2ME

18. Challenge:
UI & UX: Design Paradigm
realistic vs digital design

19. Challenge:
UI & UX: Desktop Integration

20. Challenge:
UI & UX sample: Long Lists

21. Challenge:
UI & UX: Navigation Keys

22. Challenge:
OS Versions
2.3 5.x 7.5 6.x
4.x 6.x 8.x 7.x
10
The platforms themselves evolve all the time

23. Cross-Platform Strategies
1. Native
2. HTML 5
3. ANSI C
4. Cross-platform tools

24. Native Apps
1 team per platform
Best integration
Best reach
But: most effort
Photos (left to right):
(c) Julian Fong/levork flickr.com/photos/levork/4074351034
(c) Julian Fong/levork flickr.com/photos/levork/3023757995
(c) Julian Fong/levork flickr.com/photos/levork/2697173209

25. verious.com

26. chupamobile.com

27. cocoacontrols.com

28. Native Apps
Asset Sharing
Concept & Resources
Data structures & algorithms
Code sharing of business model

29. Who’s Gonna
pay For it?!
(c) mac_filko flickr.com/photos/mac_filko/6405755185

30. App Stores
!=
Freedom
(c) Pascal/pasukaru76 flickr.com/photos/pasukaru76/3926591032

31. The Holy Grail
(c) Daniel Novta/pj_vanf flickr.com/photos/vanf/6227607167

32. ANNO 2011
(c) Do-Hyun Kim/stick_kim flickr.com/photos/stickkim/6013799664

33. ANNO 2011
Source: http://app.ft.com
(c) Do-Hyun Kim/stick_kim flickr.com/photos/stickkim/6013799664

34. “I think the biggest
mistake we made as a
company is betting
too much on HTML5
as opposed to
native.”
Source: http://www.forbes.com/sites/jjcolao/2012/09/19/facebooks-html5-dilemma-explained
photo (c) kris krüg/kk+ flickr.com/photos/kk/2326609919

35. Beware of the
Uncanny Valley
(c) Gnsin en.wikipedia.org/wiki/File:HONDA_ASIMO.jpg

36. Beware of the
Uncanny Valley
(c) Gnsin en.wikipedia.org/wiki/File:Actroid-DER_01.jpg

37. Beware of the Uncanny Valley
Source: http://en.wikipedia.org/w/index.php?title=File:Mori_Uncanny_Valley.svg

38. Beware of the Uncanny Valley
Sources: http://snippetspace.com/portfolio/iwebkit/
http://www.jqtouch.com/
http://itabbar.com/

39. Security
(c) mac_filko flickr.com/photos/mac_filko/5494761933

40. Security
Source: www.filldisk.com

41. Content Heavy
(c) Pascal/pasukaru76 flickr.com/photos/pasukaru76/5268559005

42. Content that needs Freedom
(c) Do-Hyun Kim/stick_kim flickr.com/photos/stickkim/6013799664

43. Hybrid
Super Power
(c) Julian Fong/levork flickr.com/photos/levork/4074351034

44. Native HTML5
Past Future

45. C-Level
ANSI everywhere
Wrapper for native functions
...pretty hardcore
(c) Anthony/pfarrell95 flickr.com/photos/65005341@N03/6159914280

46. Cross-Platform Tools
Games Are From Mars ApPs From Venus
Photos (left to right)
(c) mac_filko flickr.com/photos/mac_filko/5034317866
(c) mac_filko flickr.com/photos/mac_filko/5125597527

47. Game Engines

48. App Tools

49. Mono Touch & Mono Droid
C# for , and
Shared libraries for business logic
OpenTK cross UI or native UI
Full native access
Problems
Know-how for both worlds required
Targeting different OS versions at once not possible

50. Mono Touch & Mono Droid
Language Features In app In app ads Push Desktop Native UI
purchase
Verdict
For C# experts
Usefulness depends on complexity of business logic

51. Titanium
JavaScript for , and mobile web
Access to some native UI elements
Custom Titanium API
Produces native code
Problems
Stability / memory management
No DOM tree or other browser features
Featureset differs between iOS and Android

52. Titanium
Language Features In app In app ads Push Desktop Native UI
purchase
Verdict
Great for prototyping & simple apps

53. Corona
Lua script for ,
Access to some native UI elements
Custom Corona API
Bridge technology between native and Lua (Enterprise)
Problems
Very limited native access in base SDK
Very complex native access in Enterprise SDK
Featureset differs between iOS and Android

54. Corona
Language Features In app In app ads Push Desktop Native UI
purchase
Verdict
Rapid development for casual games & apps developers
Strong community

55. Tools Check
Programming language
Native integration
Native UI paradigms
Use existing libraries

56. Is it worth it?
Mobile OS
you
Your App Code

57. Is it worth it?
Mobile OS Porting Tool
you
Your App Code

58. Choosing the right
Cross-platform Strategy
how?

59. Choosing the right
Cross-platform Strategy
how?
Idea, Features & Content
Target Audience & Platforms
Competition
Marketing Budget
Developer Know-how

60. (No) Return of the Zombie Apps
Zombie Alive
Source: http://gigaom.com/europe/app-store-infested-with-zombie-software-claims-analytics-startup-adeven
Photo: (c) Mark Anderson/andertoons flickr.com/photos/andertoons-cartoons/4392594997

61. Thanks! Questions?
Sögestr. 70
28195 Bremen
Download dev guide at www.enough.de
enough.de/mdgg twitter: @enoughsoftware
Robert Virkus
twitter: @robert_virkus
robert@enough.de