This document discusses various techniques to optimize mobile apps for battery performance. It suggests reducing unnecessary background activities, deferring tasks until the phone is charging, batching network requests, limiting location updates and syncing, adjusting for connection type and charge level, and using tools like Battery Historian to monitor battery usage and identify areas for improvement. The overall message is that optimizing for battery life requires understanding how power is consumed and making strategic tradeoffs between features, performance and energy efficiency.

1. May The ‘P wer’ be with you
- Prajyot Mainkar

2. WWW.COMPANY.COM
1
2
3
Agenda For Today
#BatteryMatters
#Requests
Q & A

3. “I Care Performance”
“We got ‘awesome’ features built in the app”

4. Users Care about their Battery
Battery Life
WiFi Speed/Quality
Touch Screen
Screen/Display Size
Display Type/ Quality
Connectivity
Memory
Display Resolution
0 10 20 30 40 50 60 70 80 90 100
38%
42%
44%
46%
46%
48%
52%
72%
Source: Qualcomm Band Tracker, Market Search Group, US

5. Power Banks F.T.W

6. WWW.COMPANY.COM
Battery is Part of User’s Experience

7. Compromising for Benefits
20-30% Core Functions
70% ADs, GPS, Analytics

8. ..and this is what it should ends like
20-30% Core Functions
70% ADs, GPS, Analytics
Reduce the Battery
Consumption

9. Where does the power go?
CPU RADIOS SCREEN
Screen OFF
e.g. wakelocks e.g. syncs, n/w
activities
Background
Activities
Screen ON

10. Design Principal
Reduce Defer Coalesce
Say Minimum/ lesser
background activities
If required, defer
it to when the
phone is
plugged in
Coalesce it with
other activities to
reduce wakeup
overhead

11. Doze ( Marshmallow)
Significant Motion Detector is needed for tracking
Coalesce

12. Doze ( Android N)
Significant Motion Detector is needed for tracking

13. App Standby
System determines the state of an app is idle when the user is not actively using it. It
understands the app that is not being touched but also takes into consideration that NONE of
these should imply:
The user explicitly launches the app.
The app has a process currently in the foreground (either as an activity or foreground
service, or in use by another activity or foreground service).
The app generates a notification that users see on the lock screen or in the
notification tray.

14. WWW.COMPANY.COM
Hello GPS!
setInterval() setFastestInterval()

15. Knowing Your Location
More Accurate
More Power
GPS Provider
Less Accurate
Less Power
Cellular Network Provider Passive Provider
To Your App

16. setInterval() Dilemma?
120ms 120ms 120ms
More Accurate Data?
Saving Battery Juice
V/s

17. Location Flooding
120ms 120ms 120ms
setInterval of other
apps can affect your
app
setFastestInterval()
setFastestInterval()
20ms 20ms 20ms

18. Back off based on User Behaviour
Saves Battery
Wait 2X Longer
Sync Sync Sync
Wait 2X Longer
Exponential Backoff

19. PRIORITY_BALANCED_POWER_ACCURACY
Seeking Accuracy?
PRIORITY_HIGH_ACCURACY PRIORITY_LOW_POWER
PRIORITY_NO_POWER
Better Accuracy Better Battery

20. Do Less,When You Can
Do you really need GPS?
Approximation?
Ask the User Carry On
YesNo
YesNo
You are Safe!
Use Proximation in Action to reduce the resource usage
Less time, Less process results but still meeting user’s needs
Approximation of Pixels

21. 2. Networking for GrowthNetworking for Growth

22. The ‘Networking’ Pain
More Network
More Memory
GPS All the Time!

23. WWW.COMPANY.COM
Sync Less
More ‘Power’ to you

24. Understanding “Networking”
Do Now Server Response Data Push
Optimization is Possible

25. Think of a good time!
Uploading of Files/Songs
Cropping of Images
Loading of Data

26. Sync Smartly

27. Say ‘Bye’ to Polling
New News?
No
New News?
No
New News?
No
New News available
OK

28. Prefetch Data
A way to avoid number of independent data transfer sessions
Allows user to download all the data in a given period in a single burst &
connection, at full capacity. Reduces radio activations and bandwidth, improves
battery life and latency. e.g Music Player, News reader

29. Batch Transfer & Connections
Bundle your data transfers and create a pending transfer queue
Transfer as much data as possible during each transfer session to limit the
number of sessions you require

30. Care about Network State
WiFi will be fast and Cheap - give priority
Avoid connections if NO Network is available.
Manipulate Broadcast receivers on demand
Are you on Roaming?

31. Varying Download pattern
Modify the pattern based on connection type.Also, think behaviour type
Download more data per session on faster networks
..but involve user in this scene
Force a quicker pre-fetch

32. Monitor Charge Level & State
Dock Types
Car Desk
Low-End
(Analog) Desk
High-End
(Digital) Desk
Maximise app updates and its frequency when battery is charging
Avoid updates when charge state is discharging
Opt to update the frequency of update when charged with desktop dock
than car dock

33. Programatically control the features
Darker Color, Lesser Consumption
Brightness Level have more impact

34. WakeLock, Really?
Issue/Issues batch? Job Scheduler

35. Checking the stats
Wakelock Time
Network Time

36. Battery Historian

37. Gather Insight Action
Use the tools that help
you gather the
information - GPU,
CPU or Battery Usage
What it means, and
how it will impact your
program
Act on it and repeat!
1
2
3
The
LifecycleUnderstanding which
tool to use, to
understand what data
and then where to
look into the code

38. “Before the battle
of the fist comes
the battle of the
Performance.”

39. Pr@jyot Mainkar
Director/Androcid Media Pvt. Ltd.
(www.androcid.com)
@prajyotm /prajyotmainkar +prajyotmainkar
Thank you!