This class intends to guide you by providing an overview of some of the most popular messaging options on the Android Ecosystem, as well as some tips and tricks on how to successfully implement them in your Android apps. We’ll talk about Basic Http messaging, Google’s Cloud Messaging (a.k.a. Push Notifications) and SMS (a.k.a. Text messages), and finally we’ll touch on some newer techniques like Android’s Network Service Discovery (a.k.a. Bonjour) and WebSockets.

1. Effective Android Messaging
Juan Gomez

2. Agenda
• Intro
• HTTP
• WebSockets
• SMS (Text Messages)
• Network Service Discovery
• Review
• Q&A
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3. Eventbrite by the Numbers
Over 2 million events
140 million tickets sold
$2 billion in gross ticket sales
Events in 179 countries

4. Intro
Who am I?
• Mobile Engineer at Eventbrite
• Android Developer
• Python enthusiast
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5. Intro
Slides:
• http://lanyrd.com/profile/juandg/
• http://www.andevcon.com/slides
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6. Intro
What do you mean by messaging?
• Communications between devices
• Peer-to-Peer
• Servers are “devices”, and peers too ;)
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7. Intro
Where do I need messaging:
• IM apps
• Multiplayer games
• Enterprise apps
• Many more…
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8. HTTP

9. HTTP
• Effective Android HTTP by Jesse Wilson
• Presented at AnDevCon Boston
• http://bit.ly/1auYlY2
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10. HTTP (Native)
HttpURLConnection vs Apache HTTP client
• Apache HTTP client works better on Eclair (2.1)
and Froyo (2.2)
• HttpURLConnection is the best choice for
Gingerbread (2.3) and above
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11. HTTP (3rd-party)
Volley:
• Great performance and memory mgmt
• Poor documentation and support
OkHttp
• Improved fork of HttpURLConnection (as of 4.0)
• Great documentation and support
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12. HTTP
• It’s not full duplex
• It’s not meant for device peer-to-peer
communication
• Not ideal for low connectivity scenarios (concerts,
arenas, etc.)
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13. GOOGLE CLOUD MESSAGING
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14. Google Cloud Messaging
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15. Google Cloud Messaging
• Full duplex
• Fire & Forget
• Not always reliable
• No guarantee on time of delivery
• Relatively easy to implement
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16. Google Cloud Messaging
Two implementations:
• GCM HTTP
• Based on HTTP Post requests
• Uses JSON messages
• GCM CCS
• Based on the XMPP chat protocol
• Uses XML messages
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17. Google Cloud Messaging
Android Studio can implement a simple GCM backend for you, using Google AppEngine
• Follow instructions on:
• http://googlecloudplatform.blogspot.com/
2013/06/tutorial-adding-cloud-backend-to-yourapplication-with-android-studio_26.html
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18. WEB SOCKETS

19. WebSockets
• Full-duplex communication using Port 80
• Web Server <—> Client
• Not just for Web Browsers
• Near Real-Time
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20. WebSockets on Android
• No native Android implementation
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21. Web Sockets (3rd Party)
AutobahnAndroid
• Fully open source
• github.com/tavendo/AutobahnAndroid
• Commercially supported also
Socket.IO client for Android
• Fully open source
• github.com/koush/android-websockets
• Not very well supported
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22. SMS (TEXT MESSAGING)

23. SMS (Text Messaging)
Pros:
• Asynchronous
• Ideal for low data connectivity
• Only option when there’s no data connectivity
• Mostly free (in the U.S. and Europe)
• Supported by “dumb” phones
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24. SMS (Text Messaging)
Cons:
• Asynchronous
• No guarantee of delivery (including order)
• Limited to 160 characters per message
• Android API’s are “mostly” undocumented
• Except for the new KitKat API
!
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25. SMS (Text Messaging)
When to use them:
• IM apps (duh!)
• Device activation
• Phone number verification
• As a fallback method for other protocol
• As a coordination mechanism
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26. SMS (Text Messaging)
SmsManager
• Sending is really easy
SmsManager smsManager = SmsManager.getDefault();
smsManager.sendTextMessage(“555-123-456“, null, "hello", null, null);
!
!
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27. SMS (Text Messaging)
Receiving SMS
• It’s an undocumented API
• Implement a BroadCast receiver listening for:
• android.provider.Telephony.SMS_RECEIVED
• Bundle contains an array of SmsMessage
• Checkout the new KitKat API:
• youtu.be/mdq0R2WQssQ
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28. NETWORK SERVICE DISCOVERY

29. Network Service Discovery
• Discover services available on the local network
• Based on Apple’s Bonjour
• Multiplatform support
• Android, iOS, OS X, Linux, Windows, Printers, etc.
• Only available on API Level 16 and above
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30. Network Service Discovery
Alternatives if you’re not on API Level 16 yet:
• Use JmDNS ( jmdns.sourceforge.net)
• Centralized “check-in” Server on fixed IP
• DON’T Try to do multicast/broadcast yourself
• Not very efficient (really slooow!)
• Battery Drain
!
!
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31. Network Service Discovery
Eventbrite engineering blog:
• engineering.eventbrite.com
• Android NDS Post: http://bit.ly/1aYc6RN
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32. HOW WE USE IT AT EVENTBRITE?
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33. How we use this at Eventbrite?
Entry Manager
• Paired with a home grown solution called
“Gatekeeper”
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34. How we use this at Eventbrite?
Eventbrite App
• Social Notifications
Push notification when two of your friends are
attending the same event .
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35. We’re hiring!
If you’re interested, let’s talk after the session
eventbrite.com/jobs

36. Questions?
Download our apps:
eventbrite.com/eventbriteapp

37. Thank You!
@_juandg
jgomez@eventbrite.com