In this talk I shared the experience of the FigureRunning team in developing Apps for the Android platform, starting from Apps that were designed and developed for iOS.

1. Native Development on
iOS and Android
Jan Kroon, Real Thinks B.V.
@ mdevcon March 10, 2012

2. My Timeline
Researcher Project Manager CTO CEO CEO Business Development Entrepreneur
Universität Bern
Mathematics & Physics Phd Computer Science Management Listener Speaker

3. IMHO App Generators suck ...
If your goal is to create an amazing App
• You want to use the latest and the greatest features
• You want to test and tune performance
• You want your App to feel natural to users
So you develop a native App, and if you want to reach a
world market you develop native Apps on multiple
platforms!

4. FigureRunning App

5. Your body is the controller
compass / gyroscope accellerometer

6. iOS and Android
Xcode ~ Eclipse
ObjC ~ Java
iOS SDK ~ Android SDK
project ~ Manifest
XIB files ~ XML User Interface files
ViewControllers ~ Activities
TableViewController ~ List Activity?
Instruments ~ ....
...
Jan ~ Hugo

7. Interesting Areas
• User Navigation
• Screens
• Multi-tasking
• Inter App Communication
• Sensors
• Apple / Google Services
• Testing on Devices

8. Navigation
Ways to control an App:
• push hard buttons
• tap soft buttons, sliders, switches, ...
• gestures on content, e.g. swipe, pinch
• movements, e.g. shake to undo
• speech

9. How your brain works
• Cortex makes a model of the world on six
abstraction levels, and constantly predicts the
next input of your senses.
Jeff Hawkins: On Intelligence
• That’s why real world metaphores like
buttons, tabs, sliders etc. are useful
• That’s why consistency is important, the real
world is pretty consistent
• That’s why animations are valuable, if you
touch real world objects they often move.

10. Navigation in iOS and Android
• Apple has a tradition of writing excellent Human
Interface Guidelines, controls all software and
hardware, and bundles Apps that give a good
example. (Contacts - TableView / NavigationBar,
Music - TabBar, Weather - FlipSideView).
• Google has a hard time. It controls only part of the
software stack. Hardware manufacturers often add
their own presentation layer and bundle their own
Apps. And even worse carriers can determine to
switch off certain capabilities or refuse bundled
Apps in favor of their own Apps.

11. Android phones
HTC Sense Samsung TouchWiz Google Holo

12. Differences iOS and Android
• Android users are used to use hard buttons for “home”,
“back” and “menu”. iPhone users expect a navigation bar
with a title and a “back button” or a “tab bar” and only
use a hard button for quiting an App.
• In Ice Cream Sandwich (Android 4.0) all hard buttons
are replaced with three standard soft buttons “back”,
“home” and “task manager”.
• Apple distinguishes between a NavBar, TabBar and a
ToolBar. Google introduced an Action Bar in Ice Cream
Sandwich, that is a mix between a NavBar and a ToolBar?

13. FigureRunning Apps
tab bar

14. FigureRunning Apps
status bar
action bar
nav bar
tool bar

15. Screens
• Older iOS devices have a screen of
320 x 480 or 1024 x 768 pixels. New
iOS devices have a Retina display of
640 x 960 or 2048 x1536 pixels.
• On Android you may stumble upon
any size screen that was ever
manufactured. That makes it very
difficult to create pixel perfect
designs. It also explains why the
“menu” button is very popular.

16. Multi-tasking
• FigureRunning App should continue working, also
when a phone call is received or user chooses
another song in the Music App.
• On iOS policed multi-tasking is possible since
version 4, but only in special cases, e.g. navigation,
playing music, and task completion.
• In Android unrestricted multi-tasking has always
been available. This makes a developer’s life easy,
but comes with a performance cost.

17. Inter App Communication
• Share FigureRuns on Twitter and Facebook or send
them attached to an email.
• In iOS it is possible to do all that, without leaving the
App. (URL scheme or make own UTI for attachment)
• In Android it is necessary and normal to leave the
App and switch to Twitter App to send a Tweet or
Facebook App to put a post on a friend’s wall.

18. FigureRunning Apps

19. Sensors
• We encountered no problems at all. It was
even possible to use each other’s
algorithms.
• It seems that the closer you come to the
hardware, the more similar iOS devices and
Android devices behave.

20. Apple / Google Services
App Store ~ Android Market Google Play
In App Purchasing ~ In App Billing
iAd ~ AdMob
Push Notifications ~ Android Cloud to Device Messaging
iCloud ~ No Google equivalent?
Game Center ~ No Google equivalent?

21. Testing on Devices

22. Testing on Devices
• We are testing the Android App with a big group
of volonteers from all over the world.
• Unfortunately many crashes only happen on
specific phones.
• It is often impossible to reproduce the problems
on our own devices. So we are down to studying
crash logs.
• Clearly testing on iOS devices is a breeze
compared to testing on Android devices, due to
the fragmentation of the platform.

23. Conclusions
• Android devices differ from iOS devices mainly in
user experience and the software. The closer
you get to network, sensors or processors the
more similar the two platforms are.
• Android development differs from iOS
development in that Android development
tools are not as advanced and integrated as
Xcode.
• It is practically impossible to write an App that will
run flawless on all existing Android devices.

24. Recommendations
• Make separate User Interaction Designs for iOS and
Android versions.
• Let a “native developer” translate your App.
• Aim at a few popular Android phones, make sure
your artwork looks great on those phones and test
performance of your App on those phones. Don’t
worry about the rest.
Develop More Amazing Apps!

25. Questions?
@jankroon or jan@figurerunning.com

26. Back Up Slides

27. Similarities
• An App consists of a bundle with code files and resource files (data, texts, images, sounds)
• The App is created with a set of programming tools, named Integrated Development Environment (IDE).
Most Android developers use Eclipse, all iOS Developers use Xcode. Typical tools are editors, syntax
checker, static analyzer, simulators, debuggers, etc.
• The code is written in an Object Oriënted programming language (Android developers write Java code,
iOS developers write ObjC code) --- Objects, Messages, Inheritance, ..
• A developer can use Frameworks that are made available by either Google (for Android) or Apple (for
iOS). A Framework contains ready-made objects that a developer can integrate and use in the App. There
are frameworks for WebViews, MapViews, ListViews, Sending Email or Tweets, Showing Movies, ...
• The App is executed as a process in a Run Time Environment (RTE), that is logically separated (sandboxed)
from all other running processes. In Android this RTE is named Dalvik, a Java Virtual Machine. In iOS it is the
iOS run time.
• ...

28. Differences
iOS is much more consistent in it’s animations than Android:
• lifting one screen and taking another screen from underneath the first screen and place it on top (like
if you take a book from within a pile of books, and place it on top of the pile) is used for switching
between Apps
• a screen sliding in view from the right or left is used for moving through a hierarchy (as the result of a
tap) or to view a collection (as a result of a swipe)
• a screen that slides up and down and partially covers the original screen is the way to display utility
panels
• fading in and out of a screen, or flipping the screen is used for switching beteen screens within the
App.
Android has only recently begun to catch up with Apple in paying more attention to design and
typography. Apple is fanatical about human interface guidelines. E.g. they teach never to put “Yes” or “No”
buttons in an alert, because this forces users to read the question and may cause problems if they don’t.
Putting “Cancel” and “Delete” in the buttons is a superior approach. This attention to detail makes the
difference between “Good” and “Great”.
The run loop in iOS RTE juggles with Apps, your App is either running in the forground, running in the
background or suspended in the background. The run loop in Dalvik juggles with activities, i.e. the screens (and
what happens behind the screens) of your App or other running Apps. Android doesn’t show clearly
whether the next screen is from your own App or another App. I am often clueless about which App I am using
on Android, you get screens from Mail, Browser, Maps etc. without ever having started those Apps!

29. Inspiration
• http://mashable.com/2011/03/21/cross-platform-mobile-frameworks/
• http://www.slideshare.net/360conferences/nsnotificationcenter-vs-
appdelegate
• http://android-developers.blogspot.com/2012/01/say-goodbye-to-menu-
button.html
• http://gigaom.com/2012/02/19/clearly-its-time-to-say-bye-bye-to-buttons/
• http://watchingapple.com/2007/06/up-right-out-and-spin-iphones-animated-
transitions/
• http://www.figurerunning.com
• http://www.bgr.com/2012/02/22/google-to-sell-android-based-heads-up-
display-glasses-by-years-end/