Battery life concerns are certainly limiting Android power users and causing us to feel the need to manage our phones more than we should. JuiceDefender aims to remove this burden from the user by monitoring and managing the phone’s power usage for them.
JuiceDefender (JD) works by turning off your power-sucking data connection when you’re not using it. A series of triggers enable and disable your Wi-Fi and APN connections depending on the following: your location (Wi-Fi only), current screen use, battery level, time of day, and a schedule. The triggers are prioritized in the preceding manner. When the application is working as it should, the result is a wonderfully complex but seamless power management solution.
When your phone’s screen is off and you’re not using it, JD turns off your APN connection. But since many applications and widgets rely on background updates, you can set JD to reopen the data connection for 1 minute every 15 minutes (or other user-defined intervals). If the battery level dips below a percentage you defined, JD will turn off the connection, then turn it back on indefinitely when you charge your phone. You can save battery overnight by setting a night schedule that also turns your ringer off.
The best part is that you don’t have to do a thing. Just by installing this application and setting my preferences, my battery life has improved by as much as 1.75x (as displayed by the included widget, which also allows one-touch disabling and enabling of JD). I use my phone a lot during the day, so people who use their phone less will likely see a higher multiple.
The application isn’t perfect, though. The user interface needs dramatic improvement as it is quite intimidating in its current state. All of the controls and settings for each of the aforementioned triggers are on one screen and what each button does is not easily determined. If each trigger had its own individual screen, there would be more room for explanation and less trial-and-error while choosing your settings. If you are confused by the controls, there is an “Easy” button that will set up JD with very reasonable settings.
Occasionally, when you unlock your phone the APN connection isn’t restored. This can be quite frustrating. The developer says that this error isn’t caused by the application itself, but rather an Android bug in which the GSM cell refuses to reactivate the APN connection. Regardless, it’s an issue to be aware of when using the application.
Pros:
- Easy way to noticeably improve your battery life
- Intricate controls allow you to customize your power-saving settings
- Small widget gives you easy access to on/off controls and tells you how much battery life you’ve gained
Needs improvement:
- Cramped user interface can be intimidating and confusing
- APN connection occasionally will refuse to restart when turning on the screen
What’s next?
JuiceDefenders’ developer says he is working on a new user interface and a version of the app in which every trigger is completely customizable. No timetable has been given for the release.
Final verdict: If you’re interested in dramatically improving your battery life without doing too much manual power management, this application is definitely worth your money. After a few tweaks, this application will become truly essential.
JuiceDefender is available in the Android Market for free. The $3.76 add-on UltimateJuice is required to customize JuiceDefender’s settings. A Nexus One was used to test the application.
Note: This review was submitted by Mark Cizdziel as part of our app review contest.