App describes "Data while screen on" as "not recommended", but doesn't say why it's not recommended

[unforgettableid]

Hi!

I would like to be able to install apps and use my phone's web browser and whatnot. To do this, I guess I must enable the "Data while screen on" setting.

When I enter the "Settings > Data while screen on" menu, the fine print for that setting says: "Enable data while the screen is switched on (not recommended)". But the fine print doesn't say why it's not recommended. And even when I tap the setting, the app doesn't pop up any dialog box to tell me why it's not recommended.

I'm still clueless. It would be most excellent if you could please modify the app to inform users of why that setting is not recommended.

P.S. Thank you very much for writing, open-sourcing, and maintaining BatteryFu!

[tobykurien]

The reason it's not recommended has more to do with human behaviour than anything else. I wanted to discourage its use, because otherwise the user will tend to use the device more heavily, thus negating any benefit of using BatteryFu.

More specifically, most users tend to switch on their screens often during the day to check if there are new notifications, which would trigger BatteryFu to switch on data, which would power up the radios. Even if the data is set to switch off immediately after the screen turns off, the radios stay powered up for a while (this is controlled by the baseband processor). The result is that, combined with the sync and the likely notifications that subsequently pop up, the battery gets hammered more than if the user wasn't using BatteryFu at all. Discouraging this feature thus steers users into a more battery-friendly usage of their device.

I didn't know how to put the above into a dialog that would make sense to users and not sound condescending, so I just left it as "not recommended".

[unforgettableid]

the sync and the likely notifications that subsequently pop up

Ah. I guess the CPU and radio would exert themselves to do the sync, and then the screen would light up to show the notifications.

I didn't know how to put the above into a dialog that would make sense to users and not sound condescending, so I just left it as "not recommended".

Fair enough. There's surely a way to put it into a way which makes sense to users and is polite, but it's not obvious to me either how to do so. :) Maybe a technical writer or a usability specialist could help.

Anyway.

• It seems based on some AppBrain data that an average phone in use nowadays is a Samsung Galaxy S3 a few years old. Fine. Imagine a university student named "Fred". Fred owns an average phone, uses it in an average way, and lives in an average apartment. Each day, he usually discharges his phone to a state of charge of around 30% through ordinary use. Each night, he usually recharges his phone to 100% overnight. But today, his charger broke. He hasn't yet bought a replacement.
  • Every night, Fred sleeps for 8 hours. Every night, he leaves his phone on his kitchen counter. He keeps the phone on, and data on, and Wi-Fi on, and "Keep Wi-Fi on during sleep" enabled. In the morning, by how many percentage points will his battery's state of charge have been depleted?
  • What if he had turned data and Wi-Fi off for those 8 hours? (Knowing the answer to this will help me to know how much of a battery drain data and Wi-Fi truly are.)
• Please assume that I also own an average phone and live in an average situation. Okay. Now, please imagine that I would keep "Data while screen on" enabled, and that I would keep "Force Sync" disabled, and that I could somehow set "Delay after screen off" to a large enough value (maybe an hour, or even many hours). Would BatteryFu be likely to save me juice in the long run?

[tobykurien]

Sorry, not sure why I didn't get around to answering this, but I guess my answer is, I guess I don't know, please try and let me know your results.

On my phone, if wifi is connected, the battery drain overnight is not much, but if wifi is not connected, and my cell signal is weak, the overnight drain can be high. If I'm away from home, it's usually worse. I also don't like to be disturbed with notifications at night, so I prefer to keep data off. Different for everybody, I suppose, so I don't think that the "average" would be a good compromise.

[Klimmbimmel]

I also think the unforgettableid should have tried it on his own. But thanks for your answer.

For me the issue isn't an issue and you have found the best description. You might add something like

"Not recommended as this increases the energy consumption in most cases."

But that should be provided as a popup or something else, as it lengthens the description too much.