Android Power Calculations Approaches and Best

Practice

Hafed Alghamdi

Overview

• Why Android Devices

• Power Efficiency in Mobile Device

• Application Development Considerations

• Power Consumption Measurement Approaches

• Power Consumption Measurement Best Practice

Power Consumption Measurement Approaches

• Offline Measurement approach

• External measuring device (Ammeter)

• It is recommended to measure power with a “fake” test battery

• Most of the time fake batteries are not good enough to provide robust electrical contact.

• Online Measurement approach

• Good technique for applications developers

• Easy to use inside the code and provide reasonable results

Offline Measurement Approach

• Moonson, Agilent and other Power Monitors

• Very Expensive

• Provide accurate results

• Yoctopuce digital ammeter

• Open source management software

• It can store data in a database

• Regular Ammeter for one simple task at a time

Online Measurement Approach

• PowerTutor developed by University of Michigan (5% fault )

• Supports only HTC G1, HTC G2 and Nexus One Android mobile phones

• Little Eye

• Aimed to support all Android devices

• The company was acquired by Facebook and the tool disappeared from the internet

• Android Power Profiles

• It can be used directly in your code

• Approximation with this framework is the most accurate method for collecting power data

• Trepn™ Plug-in for Eclipse

• Easy to use

• Provide excellent results

• Little Eye

Trepn™ Plug-in for Eclipse• Benefits

• Power at battery

• CPU cores and frequency

• Network states and usage

• Display and GPU

• GPS and Bluetooth state

• Wakelock and Wifilock states

• Tool Requirements:

• Eclipse + ADT plugin

• Android SDK Tools

• Android Platform-tools

• A version of the Android platform

• A version of the Android system image for the emulator or just a device

• Android ADB interface driver

• Trepn Plugin

Power consumption measurement Best Practice

• Display brightness

• Applications and services running in the background

• WiFi, GPS, BlueTooth can drain significant amount of power.

• USB devices should be disconnected during power measurement

• Power dissipation of loudspeaker

• Avoid moving the device will activate different sensors and associated device drivers to process those sensors output.

Q&A