[Greenify] oasisfeng:
FAQ

Q: Why not support Android 2.x?

A: Sorry, Android 2.x lacks a core mechanism that Greenify mainly depends on. It's impossible to achieve equivalent functionality in Android 2.x. If possible, please consider upgrading your device to Android 4.x (CyanogenMod is a good choice if no official 4.x upgrade). If you are out of luck in upgrading, you can also try one of the alternative tools I mentioned in the app description of Greenify on Play store, such as "App Quarantine" (for most users) and "Autostarts" (for super users).

Q: Which apps should I greenify?

A: In short, don't hibernate all (or most of) your apps! App Analyzer of Greenify only shows apps which have POTENTIAL impact on battery consumption or device performance (click the icon "i" of each section for more details), it doesn't mean they actually have. You are suggested to only hibernate those you seldom use, plus the apps you are sure have negative impacts, most probably identified by the "Settings - Battery" of your device, or 3rd-party diagnose apps, such as Wakelock Detector and BetterBatteryStats (for power users).

[Background Knowledge]

"Running in background" does not mean it has definite impact on battery consumption or device performance. Experienced developers can also reduce the memory footprint of background service as low as several megabytes, which is negligible in most middle-to-high end devices with 1~2G RAM.

"May slow down the device" also does not mean it has definite impact on device smoothness. Android caches the process of apps regularly run, thus significantly reduced the cost of launching it in background.

Q: It seems that automatic hibernation is not working.

A: That is most probably caused by your root management tool. Because some root management tool require re-authorization after app update, you may have missed the confirmation dialog, since Greenify requests root privilige when screen is off.

If you are using SuperUser and confirm root privilege is granted to Greenify, there's a high chance SuperUser is not working correctly for background root privilege requests on your device. Most user with this issue got it solved by installing SuperSU instead of SuperUser. You are suggested to have a try.

Q: I want to greenify system apps!

A: First of all, it's not safe to greenify system apps, because system apps are responsible for core functionalities of your device and they are usually essential components for other apps. Android OS also protects system apps with far more privileges than mornal apps, that stops Greenify from effectively putting them into hibernation.

Q: I still want to greenify system apps, and I can accept any bad consequence!

A: If so, you can try converting non-critical system apps (such as apps bundled by carriers) into normal apps with the help of Titanium Backup or similar tools. Reboot your device, then greenify it as normal. Or you can try the experimental feature in donation version to directly greenify system apps.

Q: Degreenified apps (or greenified apps with donation package) still got no push notification!

A: Unlike iOS's pure text push messages, push notification in Android involves background task. So hibernation does stop the push notification from working. Even after you degreenfied these apps (removed from list), you may still need to reactivate the push registration in them.

Different apps have different procedures, some will automatically re-activate it, some with (push) notification settings can be easily turned off and on again, and some may need you to logout and login again.

An experimental feature "GCM push for greenified apps" (in donation package) is aimed to enable push notification for greenified apps if they use Google Cloud Messaging for push notification (a little GCM icon will show up for GCM-enabled app in App Analyzer). This can be extremely useful for some apps if your usage pattern mainly depends on the push notification from them, but don't want the overhead of background activities.

You may still need to reactivate the push registration as mentioned above if the push notification stops working occasionally.

Q: Some of my greenified apps (e.g. Google Maps) seems not hibernating.

A: In short, don't worry about frequently awake apps. It will still hibernate in minutes after screen goes off, thus hardly add observable battery consumption. Use battery statistics in settings or "BetterBatteryStats" to confirm that.

While most greenified apps will stay in hibernation quietly, some apps do break hibernation, due to being woken up by others. Some known cases include enabled account sync, backup agent, and explicit launch by other app.

Since version 1.45, Greenify will now automatically turn off directly involved account sync of greenified apps when going to hibernate, to avoid the periodic account sync wake them up. For backup agents, Greenify will NOT disable them, to ensure your backup of app data is always up-to-date. As backup usually does not perform often, they are thus unlikely to be waken up often.

Google+ and Facebook are typical example of explicit launch by other app. 3rd-party apps with Google/Facebook login wake up Google+/Facebook app when they need to use the login information.

Since Greenify is designed to not break any explicit usage of greenified apps, these behaviors are considered "normal", and will NOT be "fixed". To clear out your unease, Greenify will still put them into hibernation when standby to protect your battery consumption.

Q: Could you add an option to allow for a scheduled hibernation every x minutes?

A: I have been considering this option, but at last, I found it a task "too complicated to satisfy all". Some users need the option "night mode" which means scheduling on specific time, some users need the option "every x minutes" which means scheduling on fixed periods, and even worse when some users asked for separate schedules for each greenified app. Still, it is not the end, I received a mail asking for hibernation scheduling by network state.

Then, I realised that if the scheduling feature is implemented, not only this feature itself will be a bottomless pit, but Greenify will also become a complicate monster that most users will get stuck in tuning those options. It is obviously not my intention.

So, let's just leave the complication to professional tools like Tasker and Llama. They handle scheduling far better than I could achieve. Thus Greenify could focus on its core functionality and evolves a bit quicker, since I don't have much time developing this app.