The document provides guidelines for building efficient Android apps. It discusses minimizing permissions, bulk database updates using transactions, importing pre-populated databases, using fused location services, background data updates, being adaptive to different devices and networks, optimizing for text input and speech, geofencing, and intercepting links. The overall guidelines are to follow best practices, minimize permissions, optimize for efficiency and adaptability, and provide a seamless user experience.

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From good to awesome

9. 01
Install

10. 01
Install
02
Launch
Start!

11. 01
Install
02
Launch
03
Look & Feel
Start!

12. 01
Install
02
Launch
03
Look & Feel
04
Use
Start!

13. Step 1: Install
First touch point.

17. Minimize Permissions
• Request only core functionality blockers.

18. Minimize Permissions
• Request only core functionality blockers.
• You don't need permission to launch another App that has
the permission

19. Minimize Permissions
• Request only core functionality blockers.
• You don't need permission to launch another App that has
the permission

20. Need a contact?

21. Use the force,
Luke

22. Asking for contact
Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
intent.setType(Phone.CONTENT_ITEM_TYPE);
startActivityForResult(intent, MY_REQUEST_CODE);

23. void onActivityResult(int requestCode, int resultCode,
Intent data) {
if (data != null) {
Uri uri = data.getData();
if (uri != null) {
Cursor c = getContentResolver().query(uri,
new String[] {Contacts.DISPLAY_NAME,
Phone.NUMBER}, null,null, null)
}
}
}
Asking for contact

24. Need a UUID?
Option 1: TelephonyManager.getDeviceId
Requires READ_PHONE_STATE.
Option 2: Settings.Secure.ANDROID_ID
Reset at wipe
Follows the device, not the user.

25. Use the force,
Luke

26. Generate UUID
Use backup API

27. Step 2: First Launch
“ok, let’s see what this app is all about”

28. MyBig
BRAND

29. LOADING ...

30. A bunch of data
to insert?

31. SQLTransactions
speeds things up

32. db.beginTransaction();
try{
for(int i=0; i<selectedIds.length; i++){
values.put(COLUMN_ID,selectedIds[i]);
values.put(COLUMN_STARRED,starred);
db.insert(TABLE_STARRED,null,values);
db.yieldIfContendedSafely();
}
db.setTransactionSuccessful();
}
finally {
db.endTransaction();
}
Bulk DB update

33. Not fast enough?

34. Server Side
● Create a db file using SQLite and
fill it.
● Name your primary key columns
“_id”
● Create a table:
“android_metadata”
● Insert a single row containing the
locale (ex: "en_US")
Import ready
to use DB

35. Mobile Side
● Grab the zipped DB from assets
or network.
● Unzip it to your getDatabaseDir()
● Use as usual
Import ready
to use DB
SQLite version

36. Step 3: Look & Feel
“Where is the share button?”

38. HOTMAIL

39. OUTLOOK.COM

40. HOTMAIL OUTLOOK.COM

41. Follow the guidelines

42. LOOK AND FEEL

43. LOOK AND FEEL

44. LOOK AND FEEL

45. LOOK AND FEEL

46. LOOK AND FEEL

47. LOOK AND FEEL

48. Follow the guidelines
Please

49. Step 4: Daily Use
“I really like it, but...”

52. Always up to date
Users don't like to wait.
• Location updated.
• Data downloaded from web.

53. Always up to date
Users don't like to wait.
• Location updated.
• Data downloaded from web.

54. Find the location fast.
• Loop through all providers->getLastKnownLoc.
• If there is one or more location which is recent enough – return the most
accurate one
• If not – Return the latest one.
• In case of #2 – look for “fastest” provider:
• Coarse Accuracy && low power consumption.
• Register for location update.

55. Use passive location
• >Gingerbread.
• Passive location – Receive location update when other app is using
location provider.
• Requires ACCESS_FINE_LOCATION permission.
• Location.getProvider().

56. Fused Location
• Define your priorities
• Let Google play services do the heavy lifting.

57. // Create an instance of GoogleAPIClient.
if (mGoogleApiClient == null) {
mGoogleApiClient = new GoogleApiClient.Builder(this)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.addApi(LocationServices.API)
.build();
}
Using fused location

58. @Override
public void onConnected(Bundle connectionHint) {
//get last known location
mLastLocation = LocationServices.FusedLocationApi.getLastLocation(
mGoogleApiClient);
if (mLastLocation != null) {
//do something
}
//register for location updates
LocationRequest request = LocationRequest.create();
request.setInterval(minTime);
request.setPriority(lowPowerMoreImportantThanAccuracy ?
LocationRequest.PRIORITY.BALANCED_POWER_ACCURACY :
LocationRequest.PRIORITY_HIGH_ACCURACY );
LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient,
request, this);
}
Using fused location

59. @Override
public void onLocationChanged(Location location) {
mCurrentLocation = location;
mLastUpdateTime = DateFormat.getTimeInstance().format(new Date());
updateUI();
}
Using fused location

60. Data updates

61. The challenges:
• When to update?
• Where the data is coming from?
• What to update?
• How to update?

62. When to update my App?
• Right before the user launches it
• Assuming I have battery.
• Assuming I have BW.

63. Where the data is coming from?
• My Server
• 3rd
Party Servers

64. Where the data is coming from?
• My Server
• 3rd
Party Servers

65. What to Update?
• What's Hot
• Interesting stuff
• Other

66. BG Update
What's Hot
BG Update
Interesting
Stuff
Other

67. BG Update
What's Hot
BG Update
Interesting
Stuff
Other
FCM
Embedded

68. BG Update
What's Hot
BG Update
Interesting
Stuff
Other
FCM
Embedded
FCM +
Back-off

69. BG Update
What's Hot
BG Update
Interesting
Stuff
Other
FCM
Embedded
FCM +
Back-off
Daily /
Bundled

71. Being Invisible
• I don't need to think how the app works.
• I never notice the app's work.
• I am never being bothered by the app.

72. Work Offline
Queue and Send transactions.
• Use persistence layer.
• Tape From Square.

73. Work Semi-Offline
• Be resilient to poor networks.
• Prioritize your transactions.
• Be able to cancel transaction on the fly, or clear the Queue.
• Adjust your app’s behavior and timeouts accordingly.
• Use Volley (or any other cool transport layer)

74. Be efficient – Data usage

76. Radio Resource
• Frequency is expensive.
• Cell tower can not service 100% of its clients 100% of the time.
• Frequency is dynamically allocated to clients.
• Cellular cells uses various multiplexing methods (OFDM/OFDMA,
FTDMA).

77. UMTS RRC States. (source: 3gpp)

78. Radio State Machine
IDLE
FACH
DCH
Power
Bandwidth

79. Radio State Machine
IDLE
FACH
DCH
Power
~10Sec tail time
~12-75 Sec tail time
Bandwidth

80. Avoid bursty traffic
• Transmit data “together”.
• Piggyback if needed.
• Pre-fetch data for the next 2-5 minutes.
• Don't ping just to keep TCP connection alive
• RRC != TCP Connection.
• TCP connection is kept even in IDLE mode

81. #1: Case study: Pandora
• Music file streamed as single file.
• Analytics data sends ~2KB every 62.5 seconds
Source: AT&T research

82. #1: Case study: Pandora
0.2% of data consumed 46% of energy!

83. Don't be HTTP rookie
• Don't download what you already have.
• Take care of server headers
• Max-age, expires.
• Use conditional GET when cache expires
• Use “last modified” header.
• Server return 304, with no body.

84. Don't be lazy
• Read AT&T research:
• Top Radio Resources Issues in Mobile Applications
• AT&T Lab Research – call for more efficient apps
• Watch my BABBQ talk - Building battery efficient apps
• (or ask yonathan to invite me once more ;-) )
• Use ARO.
• Developed by AT&T.
• Monitors and analyze network activity.
• http://developer.att.com/
• https://github.com/attdevsupport/ARO

86. Adaptive App
• Optimized for different User Experience.
• User has more than one device.
• Be predictable.
• Behave as expected

87. Text Input
• Specify the Edit Text input to show the right keyboard type.
• use android:inputType attribute
• Four classes of keyboards:
• Plain text
• Decimal Number
• Phone Number
• Date or Time

88. Text Input
• Plain text types:
• URIs
• Email address
• People's names
• Postal address
• Passwords

93. mGeofenceList.add(new Geofence.Builder()
// Set the request ID of the geofence. This is a string to identify this
// geofence.
.setRequestId(entry.getKey())
.setCircularRegion(
entry.getValue().latitude,
entry.getValue().longitude,
Constants.GEOFENCE_RADIUS_IN_METERS
)
.setExpirationDuration(Constants.GEOFENCE_EXPIRATION_IN_MILLISECONDS)
.setTransitionTypes(Geofence.GEOFENCE_TRANSITION_ENTER |
Geofence.GEOFENCE_TRANSITION_EXIT)
.build());
Geofencing

94. private GeofencingRequest getGeofencingRequest() {
GeofencingRequest.Builder builder = new GeofencingRequest.Builder();
builder.setInitialTrigger(GeofencingRequest.INITIAL_TRIGGER_ENTER);
builder.addGeofences(mGeofenceList);
return builder.build();
}
Geofencing

95. private PendingIntent getGeofencePendingIntent() {
// Reuse the PendingIntent if we already have it.
if (mGeofencePendingIntent != null) {
return mGeofencePendingIntent;
}
Intent intent = new Intent(this, GeofenceTransitionsIntentService.class);
// We use FLAG_UPDATE_CURRENT so that we get the same pending intent back when
// calling addGeofences() and removeGeofences().
return PendingIntent.getService(this, 0, intent, PendingIntent.
FLAG_UPDATE_CURRENT);
}
Geofencing

96. LocationServices.GeofencingApi.addGeofences(
mGoogleApiClient,
getGeofencingRequest(),
getGeofencePendingIntent()
).setResultCallback(this);
Geofencing

97. private void initTextToSpeech() {
Intent intent = new Intent(Engine.ACTION_CHECK_TTS_DATA);
startActivityForResult(intent,TTS_DATA_CHECK)
}
Geek Magic - Text to speech

98. private void onActivityResult(int request, int result, Intent data) {
if (TTS_DATA_CHECK == request && Engine.CHECK_VOICE_DATA_PASS == result) {
tts = new TextToSpeech(this, new on InitListener() {
public void onInit(int status) {
if (TextToSpeech == status) {
ttsIsInit = true;
}
}
});
}
else {
startActivity(new Intent(Engine.ACTION_INSTALL_TTS_DATA));
}
}
Geek Magic - Text to speech

99. private void say(Strint text) {
if (null != tts && ttsIsInit) {
tts.speak(text,TextToSpeech.QUEUE_ADD, null);
}
}
Geek Magic - Text to speech

100. private void requestVoiceInput() {
Intent intent = new Intent(RecognizerIntent.ACTION_RECOGNIZE_SPEECH);
intent.putExtra(RecognizerIntent.EXTRA_LANGUAGE_MODEL,
RecognizerIntent.LANGUAGE_MODEL_FREE_FORM);
intent.putExtra(RecognizerIntent.EXTRA_PROMPT,
getString(R.String.voice_input_prompt);
intent.putExtra(RecognizerIntent.EXTRA_LANGUAGE,
Locale.ENGLISH);
startActivityForResult(intent,VOICE_RECOGNITION);
}
Geek Magic - Speech Recognition

101. private void requestVoiceInput() {
Intent intent = new Intent(RecognizerIntent.ACTION_RECOGNIZE_SPEECH);
intent.putExtra(RecognizerIntent.EXTRA_LANGUAGE_MODEL,
RecognizerIntent.LANGUAGE_MODEL_FREE_FORM);
intent.putExtra(RecognizerIntent.EXTRA_PROMPT,
getString(R.String.voice_input_prompt);
intent.putExtra(RecognizerIntent.EXTRA_LANGUAGE,
Locale.ENGLISH);
startActivityForResult(intent,VOICE_RECOGNITION);
}
Geek Magic - Speech Recognition

102. Geek Magic – Speech Recognition
• More than one result is returned.
• Loop through all results, taking context in mind.

103. <intent-filter>
<action android:name="android.intent.action.VIEW"/>
<category android:name="android.intent.category.DEFAULT"/>
<data
android:host="mysite.com"
android:scheme="http"/>
</intent-filter>
Intercept Links

104. Follow the
guidelines
Be Fresh
Be Invisible
Be Efficient
Be Adaptive
Be Psychic
Make it
quick
Start!
minimize
permissions

105. Thank You!
+RanNachmany
@shed2k