High energy consumption of email app

I recognized that the email app consumes quite a lot of battery power. I think so because it is used only for a couple of minutes but consumes more battery then the phone app for calls which surprises me a bit.

Can someone confirm this behavior? I run latest /e/ os 1.5 on a FP4.


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Same things for me. I lose 1% every 4/5 minutes on standby because of that. Murena One v1.5

When an email app consumes a lot of energy this can have several reasons.

Typical is that the mail app polls the mail servers for new mails in very short intervals up to every five minutes or so. This costs a lot of energy, especially when there’s no wifi connection. Setting the polling interval up to some hours or polling the server manually is much better related to energy consumption.

This polling costs also more energy when the Inbox is rather filled. Some people never clean up. But some mail clients check new mails on the client side, this means all the mails in the Inbox are pumped again and again, including attachments (this costs also a lot of bandwidth and data volume). So cleaning a POP3 Inboxes is a also good idea.

Some people have polling activated while also the IMAP push mechanism is active. This polling is then completely senseless but requires a lot of energy.

Generally it’s much better to use the IMAP push mechanism. This requires only very short keep alive messages to the server every some ten minutes.

After an OS (or app) update I would check if something has changed in the configuration of the e-mail accounts.


I’ve only 1 mail account like murena.io. no gmail or other. Your answer is wrong for my issue

Did you understand what I wrote?

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I have 3 accounts configured, all IMAP. My inboxes are quite clean but I disabled sync and set it to “never” (was 15 minutes). So only the IMAP push will trigger a sync from now on. I will monitor this to understand if this changes anything and will report.


This sounds all good.

Now clean also the cache of the Mail app (only the cache!) There may still be data from before which can be not good anymore. This will not affect the configured mail accounts but can have an impact on the energy consumption.

That fixed it!

Special thanks @irrlicht :grinning:

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I wondered on poll vs push if the poll interval is set so short by default, that quoted 15min of yours - but on newly set IMAP accounts I see them set to 24h … so I’m glad for the sensible default :slight_smile:

I tried to remember if it was me who set that 15 min interval but I can’t… However, disabling the sync interval completely works perfectly fine here. Also, the app cache was cleaned as suggested.

It’s a shame that many mail apps do not handle this topic as it would really be needed. I guess this comes because they all start with polling (to handle POP3 and IMAP servers in the same way) and then implement the IMAP push mechanism later. So the options screen is mostly designed for cyclic polling and gets some entries later for push, I mean: additionally, not clearly separated, often made by another developer. The result is all mixed, hard to understand and after all confusing when you are not experienced with these technologies. The stock mail app has it this way because K-9 is not good related to this, FairEmail is also not really better in the settings.

But indeed it’s simple: The first question the user must get while setting up a mail account is: POP3 or IMAP? And in case of IMAP he must get a second question: polling or push? Push should be the default, polling should only be used in the rare case that the IMAP server doesn’t support push. This should be told to the user in clear words. And according to the answers to these simple questions three different ways with each only a handful of options would be needed to configure this once for all correctly.

I guess many people could get much better working mail accounts in their mail apps, needing less accu and bandwidth.


/e/ v1.6 will come with this change - 5137-Update_default_folder_poll_frequency (!114) · Merge requests · e / os / Mail · GitLab

haven’t reviewed what the 60min->5min interval change applies to. When I created a new account it seemed to be 24h for me, but maybe it’s a value I did set globally at some point in the past and I’d need to test from factory reset

From what I understand, the minimum interval for background polling is 15 minutes. An app can request intervals less than 15 minutes, but the system will enforce the 15 minutes restriction. For more frequent updates mail apps should use PUSH. Both /e/'s Mail app and K-9 Mail (from which /e/'s Mail is forked) support PUSH

My understanding is based on several posts in the K-9 Mail community forums

Yes, sure, but many people don’t know that, can’t imagine the difference and will not configure it correctly because many mail apps don not make it clear.

Just a by-the-way: Mozilla is currently revamping K-9 and are planning to rebrand it as Thunderbird for Android. See https://blog.thunderbird.net/ for some details. I’m sure they will be interested in ideas for improved usability.

I also noticed that the Mail app consumes a lot of power. I don’t use the Murean account at all, Protonmail has its own app, I only use it on a daily basis.
I am currently running a /e/OS 1.8-s-20231207360611-stable-FP3 android version on the phone.

This battery usage happened on 19 December:

And this battery usage happened last night:

Please help me, where in the Mail app should I set this option?
Thanks in advance for your help.

If you are sure your mail server is an IMAP server, try the following:

  • in the Mail app open the settings
  • select your account (I mean: open account specific settings)
  • select the “request e-mails” section (3rd from top)
  • set the polling interval to “Never (only manually)” - this means: no polling anymore from now on

Now, send yourself an e-mail, use a PC or whatever for that. Your mail server should send you a push notification in just a few seconds, much faster than polling detects your received mail message. If you don’t receive a push notification you have either still a configuration problem on the client side or your mail server isn’t able, can also happen in rare cases.

If you have mail accounts on multiple IMAP servers you must configure (and check) each one this way.

A precondition is that background synchronization remains switched on. This is a general setting in the Mail app outside of the accounts in the “Network” section.

There are still more settings for fine tuning but turning off the cyclic polling should do the general change in the behavior and reduce the energy consumption and the network traffic a lot.

Clear your app cache once, just to be sure.

Thank you, it’s working :slight_smile: