Minimise battery use

[beaky]

I have a number of apps including aquamail that have the potential to prevent the tablet sleeping.
Clearly I will have to address each one in turn, but I wonder if it would be helpful more generally if you could indicate which of the settings cause activity to continue when the screen is off, such as by keeping the WiFi active.
When my tablet was brand new, there was little activity when the device was sleeping. Not so any more (to be fair also under the influence of many other apps). In particular, the WiFi is on most of the time.
But the longest journey starts with a single step, so what I am asking is:

For Aquamail, which of the settings have potential to prevent the device sleeping?
Should I dispense with push for example? Settings already allow me to disallow periodic sync when screen is off, I think.
Ideally app by app I hope to get sufficient info to allow me to set them so the tablet does indeed sleep, thus extending battery life, particularly with light use, where the screen is not on very much in the course of each day...

[Kostya Vasilyev]

Push is the number one battery burner.

You might find this amusing (and supportive of my assessment):

http://www.emailsfromstevejobs.com/2010/06/06/imap-idle-support-its-a-power-hog/

Within push, the things that matter are: the total number of folders (across all accounts) in push mode, and the "messages per page" setting (how many recent messages to keep up to date).

Finally, I recommend looking at total battery use, as seen in the device's system settings / battery, and not worrying too much about the number of wake lock acquire / release transactions (popular in third party optimizer apps).

[beaky]

Push is the number one battery burner.

You might find this amusing (and supportive of my assessment):

http://www.emailsfromstevejobs.com/2010/06/06/imap-idle-support-its-a-power-hog/

Within push, the things that matter are: the total number of folders (across all accounts) in push mode, and the "messages per page" setting (how many recent messages to keep up to date).

Finally, I recommend looking at total battery use, as seen in the device's system settings / battery, and not worrying too much about the number of wake lock acquire / release transactions (popular in third party optimizer apps).

Indeed I am not too concerned about repeated 'wake'. It only uses significant power if awake for long periods. However, as i have described below, even in active use, the 'awake' trace is insignificant. What I am seeing is the WiFi on for long periods when the screen is off. As I use the tablet quite heavily with the screen on most days, it is not an issue as the screen is the biggest hog. I suspect it will be a problem if I have the device 'idle' most of the time.
Actually the layout of the battery display screen is less than obvious, with the captions and bars rather crushed together. Not sure if all android devices are like this.
There are bars for:
WiFi
Awake ( which I take to be a STATE of 'awake', not a TRANSITION - 'awaken')
Screen on
Charging

Take today, for example. The tablet was charged overnight but not turned right off. It has been off the charger for 1 hour 40 mins.
I pulled out the power plug half an hour before using the device. The battery display shows the WiFi on for 15 mins or so after pulling the charger plug, then off for another 15 or so. Then I opened the cover, the screen and WiFi both on, right until now. The device was not moved until then. If not aquamail, most likely something else was holding the WiFi on for that first 15 minutes. It seems likely that something in aquamail does come to life when charging, as it is not uncommon to hear the sound of a new email up to a minute after plugging in the charger.
The 'awake' trace is almost blank, with little spikes now and again. This is counterintuitive!
I have had the screen open and using it for one hour and ten minutes yet it is hardly ever awake?
Anyway, I do have push enabled, and will try turning it off. I am checking three accounts, and I don't have more than a standard number of folders (I am not using rules on the server to put mails in different folders).

Interesting email...

Dave

[Kostya Vasilyev]

AquaMail checks mail on a regular schedule, whether the device is plugged in or not, and regardless of its connection type (unless configured to sync mail on WiFi only, use push on WiFi only, check mail based on events, etc.... but let's keep to the default settings).

Moden Android versions are preconfigured to never completely turn off WiFi in sleep mode -- rather, they use a special power-saving mode at the hardware level when the device is sleeping.

I'm attaching two battery use screenshots from a Galaxy Nexus, 4.3, which sits on my desk all the time and is connected to my home WiFi router a few feet away. As you can see, AquaMail's battery use is quite moderate (5 accounts, no push), and so is WiFi's, despite being on all the time.

[beaky]

AquaMail checks mail on a regular schedule, whether the device is plugged in or not, and regardless of its connection type (unless configured to sync mail on WiFi only, use push on WiFi only, check mail based on events, etc.... but let's keep to the default settings).

Moden Android versions are preconfigured to never completely turn off WiFi in sleep mode -- rather, they use a special power-saving mode at the hardware level when the device is sleeping.

I'm attaching two battery use screenshots from a Galaxy Nexus, 4.3, which sits on my desk all the time and is connected to my home WiFi router a few feet away. As you can see, AquaMail's battery use is quite moderate (5 accounts, no push), and so is WiFi's, despite being on all the time.

Well, that lets off aquamail - with today's use - 10h 51m 10s on since full charge, and I have
Screen 84%, media server 8%, android system 3, android OS 3, calendar 2, tapatalk 4 2.
Aquamail doesn't make it to the short list.
Today's use involved a few quick checks of mail, a lot of use of calendar and tapatalk.
I can see that the WiFi runs for between 15 and 30 mins after shutting down the screen, but seems to extend if I move from one WiFi point to another during that time.
Also, though GPS is on all the time, it only shows activity when the tablet actually moves. Today I know when I moved it, and that is when GPS wakes up....

Somebody has done a great deal of work to make stuff sleep. I bet there is little happening between keypresses as I type this! Respect - but I bet it makes your job harder.

So my current target (using the method of moments) is to find out more about media server. Aquamail seems squeaky clean for the heavy use profile my tablet has....

Thanks for advice...

[Kostya Vasilyev]

Thanks for the detailed update, glad to hear I'm off the hook