GreenDroid Research Project
Contact: andrewust@cse.ust.hk

Problems detected by GreenDroid

In our controllled experiments, GreenDroid detected 14 real energy problems. We list the details of these problems (including some direct URL links) such that interested researchers can investigate them for further research or replicate our study.

1. Existing problems

GreenDroid detected 12 energy problems that were confirmed before our experiments. These problems are:

Application name
Energy problem
Problematic version
Problem type
DroidAR
Issue 27
Revision 204
Missing sensor deactivation
Recycle Locator
Issue 33
Revision 68
Missing sensor deactivation
Ushahidi
Commit 337b48f
Revision 9d0aa75
Missing sensor deactivation
Sofia Public Trasport Nav.
Issue 76
Revision eb4fbcb (115)
Missing sensor deactivation
AndTweet
Issue 29
Version 0.2.4
Missing wake lock deactivation
EbookDroid
Issue 23
Revision 137
Missing wake lock deactivation
BabbleSink
Commit 9fbc6f0
Revision 12879a3
Missing wake lock deactivation
CWAC-Wakeful
Commit c7d440f
Revision d984b89
Missing wake lock deactivation
Sofia Public Transport Nav.
Issue 38
Revision 7959b87 (114)
Sensory data underutilization
Osmdroid
Issue 53
Revision 750
Sensory data underutilization
Zmanim
Issue 50/56
Revision 322
Sensory data underutilization
Geohash Droid
Issue 24
Version 0.8.1-pre2
Sensory data underutilization

These problems are known to cause huge energy waste and great inconvenience for users. Below are two user reviews for Zmanim and Geohash Droid, respectively.
zmanim review
geohash droid review

2. New problems

GreenDroid also detected two new energy problems that were previously unknown. We then submitted bug reports to developers and the two bugs have been confirmed by developers.

Application name
Energy problem
Problematic version
Problem type
Omnidroid
Issue 179
Revision 863
Sensory data underutilization
GPSLogger
Issue 7
Revision 15
Sensory data underutilization

Below are two comments from developers for Omnidroid issue 179 and GPSLogger issue 7, respectively.

Omnidroid: "Completely true, and your suggestion is a great idea and you're correct omnidroid does suck up way more energy than necessary as a result.  I'd be happy to accept a patch in this regard."

GPSLogger: "Why would someone keep polling GPS if the location data are continuously discarded? GPS is an energy hog! The current design is far from perfect."

We also created a patch for GPSLogger to optimize its energy consumption. We did some field testing of our patch and the result suggested that there is around 20% energy saving. Although this saving is not too much, considering users typically concurrently run multiple applications on their smartphone, it is still meaningful if the energy consumption for each application can be reduced by 20%. This patch was later integrated into GPSLogger and a new version can be downloaded here.