Jimmie's Guide to Optimizing iPhone Battery Life

Do you find that you are having to charge your iPhone more often than you might have expected? You might be surprised to learn that there are lots of processes that are constantly drawing battery power, even when you are not using the device. If so, this article should be helpful in helping you eliminate many of the unnecessary activities.
If you find that your iPhone (especially iPhone 15) is warm when you pick it up, then this article just might be a device lifesaver!

NOTE: As a bonus, elimination of many of these items will reduce unnecessary Cellular Data usage
AND, As an additional bonus, elimination of many of these items will significantly protect your Privacy.

Settings Changes for Reducing Battery Drain

These settings are presented in the order they appear in "Settings". And no, I don't have an answer for why the iPhone Settings are NOT in alphabetical order!

I have marked the categories which are considered stronger battery drains with "(BIG)"

iCloud

BIG (sync Photos) The decision for using iCloud Backup is of course your call. This can handle things like Contacts, Messages, Settings, and the like. But Photos are another matter entirely. The business of "synching" photos to iCloud is extraordinaly complex. I have a bit more extensive commentary on all this at the bottom of this article. But in summary, I would assert that "Sync" can be at times a very destructive word!
P.S.: I simply transfer all my photos to my Windows PC, usually each time I take a set of photos, After doing so, I delete them on the iPhone.
iCloud. . .Apps Using iCloud. . . Photos

Under iCloud. . .Apps using iCloud, I have everything OFF. Battery-wise, disabling Photo-to-iCloud in particular will likely result in less battery drain because there is less internet activity every time you take photos.

When you select "Photos" under Apps Using iCloud, you will get this screen. Turn off "Sync this iPhone".
You should make sure that "Shared Albums" is also off. If you want to share photos with others, you can turn this on, but it is a BIG battery drain. Further, if you later turn it off, you will be forced to delete all shared photos (you can't turn it off otherwise).

Bluetooth

If you only pair your device with your car or other devices infrequently, you might turn Bluetooth OFF.
Settings. . .Bluetooth

Cellular

(BIG) Specify which apps or built-ins can use cellular data
Settings. . .Cellular

There is no need for things like "App Store", "Calendar", "Contacts" and the like to be using Cellular Data. You can turn most of them off. This saves you from the headache of finding yourself billed with excessive Cellular Data usage.
Battery-wise, Cellular operation is also a big battery drain; it's using the phone's radio transmitters and receivers.
Here's the first entries in the long list.

And here are the rest of the entries.
Note that "WIFI Assist does not mean the WIFI will assist the cellular coverage in weak cell areas. It means Cellular will assist the WIFI when the WIFI signal is weak!! (I had it backwards in my interpretation when I first saw it.)
NOTE: Right below "WIFI Assist" is "iCloud Backup"! (It doesn't show in this image.) Make sure it's OFF! You sure don't want iCloud to be consuming both Battery power and Cellular Data by transmitting over the Cellular network.

Personal Hotspot

When you select "Personal Hotspot", the next screen offers "Allow others to Join". If you don't anticipate providing internet access to "other devices signed into your iCloud account", set to OFF.
Settings. . .Personal Hotspot

Notifications

It's probably necessary to have only a handful of apps/built-ins to be able to send notifications to the home screen.
Settings. . .Notifications

I turned off Siri Suggestions, since I don't use Siri.
For all others, it's your call. In my case I enabled only the Alaska Airline app, Find My, and Home. Mail might be a good choice for those who use their email on their phone regularly.
Note that there is (tiny) text below each category that shows the status. You don't have to click the arrow to find out (like I did).

And here are the remaining categories. I did enable Messages, Phone, Reminders, and Southwest Airlines.
Also, I did leave all the government and safety items enabled.

Sounds and Haptics

This is a minor sounding item, but it can help in reducing battery drain. "Haptics" is the creation of a vibration when certain events ocurr. At the present time, this requires a small electromechanical device in the phone. This involves using more battery power than would be used when the vibration is turned off.
If you work in a noisy environment, it might be well to leave Haptics on for ringtones and/or alerts. But one item that keeps being mentioned in articles about battery drain is the suggestion to turn off haptics for "keyboard" use. No particular reason to have a vibration ocurr each time you type a letter or number.
Settings. . .Sounds and Haptics

We show here:
"Haptics" is set to Never Play for Ringtones and Alerts.
"Keyboard Feedback" is set to "Sound" only.

Background App Refresh

(BIG) This is usually enabled. It means all applications, including built-in or ones that you have purchased, can "update their contents" at all times the device is on, as a "background" process. This can be a big battery drain, particularly if you have a few ad-prone apps. I suggest that this be turned OFF.
Settings. . .GENERAL. . .Background App Refresh
And no, I have no answer - nor can I find an answer - for why Apple has selected a handful of setting and placed them under "General"!

This is the appearance if Background App Refresh is OFF. They're all off, and you don't have to be concerned about excess activity.

You can turn Background App Refresh ON, if desired. You can choose whether to allow this background activity to ocurr only when Wi-Fi is available, or both Wi-Fi plus Cellular. I suspect that in many cases the selection of "Wi-Fi plus Cellular" might result in excessive Cellular Data at times.
Here I show Background App Refresh to be ON (Wi-Fi only). When on, you can still restrict the activity to just selected apps. In this example, I chose Alaska Airlines and Southwest Airlines.
(Actually, after making this screenshot, I turned Back-
ground App Refresh back OFF. I only fly a couple of times a year.)

Keyboards, Language and Region

Here are a couple of minor tweaks that will help with battery drain. (Actually the second may not quite be so minor.)
Settings. . .GENERAL. . .Keyboards
Settings. . .GENERAL. . .Language and Region. . .Live Text

Keyboards: Unless you intend to use speech instead of typing, you could uncheck "Enable Dictation.".		Language. . .Live Text: "Live Text" will search for text in any of your photos that have text within them. If it finds several text areas, you touch the one you want. It will then extract that text and treat it as if it were an actual text string, allowing you to copy it or even look up the meaning of the text. It is said to also be capable of finding text in any object that you are point the camera at. I could not get this to work.	Here we see that it has correctly identified the text in one of my photos. Note the blue circle in the lower right. This is showing that Live Text is active. So if you find that you are seeing this icon from time to time, it's because Live Text is on. Unless you feel this is useful, consider turning it off. I show it off in the middle image. I suspect that this sort of pattern recognition takes quite a bit of computation and therefore is likely a bit of a battery drain whenever you are looking at photos or using the camera.

Display and Brightness

(BIG)
Settings. . .Display and Brightness

As you can see in the screenshot, I keep my Brightness just below the center point. Having the setting excessively bright will be a pretty big battery drain. Of course the display shouldn't be too difficult for you to comfortably see.
"Automatic Brightness" and "Night Shift" seem to be fairly neutral.
Personally, I leave "Auto-Lock" at the maximum - 5 minutes. I find the display being turned off every minute or so to be VERY irritating!
"Raise to Wake" should be off (unless you find this to be really convenient, of course). In order for Raise to Wake to work, a process must be going on all the time to detect when you have picked up the device.
"Always On": "Always On" is, well, "on"! This means the display is always using battery power all the time, even though the display might be dim. Note that turning it off will automatically turn off "Show Wallpaper" and "Show notifications"

Standby

"Standby" will display selected items - such as a clock, calentar, or a "widgit" - when it is turned on its side while charging. Clearly this will consume some battery power and you can consider disabling it.
Settings. . .Standby

Siri And Search

(BIG) When you have Siri enabled, the device must run a constant process to poll all sounds to find possible voices, and all voices for the sound "Siri". That's quite a lot of processing power and therefore a significant battery drain.
Settings. . .Siri and Search

We see here that I have disabled "Listen For (Siri)".
Also, there are options for "Suggestions". I have left on "Show Suggestions and "Show Recents", mainly because I am not quite know what these mean. But I did disable all "Suggestions from Apple"

Privacy Alert.
Under "Siri and Search", if you scroll down, you will find at least 20 or so different applications. When you click on any of these apps, there are four toggles that are ON by default. Turning off Siri does not turn them off.
If you find that you are getting "coincidental" ads for things that you might have been talking about in casual conversation with your phone nearby, this is why!
You actually have to select each and every app to disable the four choices. In addition to being a privacy issue, this extra activity is also a battery drain.

Privacy and Security. . .Location Services

(BIG - Battery Drain and Privacy) This category is complex, and has a lot of battery drain activity. Many of these "services" require the devices GPS
and can also use a fair amount of Cellular Data. Further, it's under "Privacy and Security" for a reason: there's a lot of tracking going on here!
Settings. . .Privacy and Security. . . Location Services

If you select "Location Services" from the "Privacy and Security" page, you get this. Here you have a button to turn all location services ON or OFF. I have this to ON, because a few things need to have location access: Compass is set to "while using" Google Maps is set to "while using" Apple Maps is set to "Never" since I only use Google Maps Everything else is "Never" NOTE: If you set "Camera" to Never, you accomplish several things: Battery drain - the device has to use the GPS every time to embed geographical information into each photo "Unnecessary" activity - You stop "Photos" from spending compute time to constantly sort your photos into "Places", "Memories", and the like. Privacy - This Location information is no longer available to any other app that might just happen to want it.		Underneath "Location Services", you will find "Location Alerts" and Share My Location (see left image): "Location Alerts": When selected, it displays "Show Maps in Location Alerts". Seems OK to leave this checked. "Share My Location": When selected, it displays "Find My(!). Here you can choose to keep "Find My iPhone" on, if desired. But "Share My Location" should be off, for battery life and privacy reasons, since it will use both your GPS and Cellular Data. This, of course, is unless your DO want to share your location with friends and family.
At the bottom of Location Services is "System Services." Selecting this allows you to check or uncheck each one. "Cell Network Search": is used for cell tower tracking for product improvement. Doesn't help you place calls "Compass Calibration": Does improve Apple or Google maps get accurate location. Device Management: Used mainly in corporate settings. Home Kit: Used only if you want automatic things to happen when you approach your home. Motion Calibration Used mainly for health activities, usually with iWatch. Network, Wireless: Similar to Cell Network Search. Not needed for your purposes. Share My Location: Note that this also appears under "Find My" in the right side image just above these two. Make sure it's off here under "System Services" as well.. Significant Locations: See next image.		"Significant Locations" yields this dialog. This is likely a BIG battery drain, since your device is contantly using the GPS to track all the places you visit. So you might leave this OFF. Product Improvement: "iPhone Analytics" does help Apple find out how their products are being used. I don't know how often data is transmitted. It's your call, but see the two images below as well! But the other two can easily be left OFF.

Analytics And Improvements and Apple Advertizing

Settings. . .Privacy and Security. . . Analytics and Improvements
Settings. . .Privacy and Security. . . Apple Advertizing

If you scroll to the bottom of the "Privacy and Security" page, you will see "Analytics and Improvements". See the image on the right for more information (and eye-opening details!)
Right below "Analytics and Improvements" is "Apple Advertizing". I think we all know what to do with this choice!

NOTE: All the 17 or so entries just above "Safety Check" do not appear to have settings choices, and are for information only. You can see the bottom four of them in this image: Media and Apple Music, Files and Folders, Motion and Fitness, Focus.
Most of these, when selected, say "Apps that have requested to use XXX appear here."

"Analytics, Improvements":
While all of these might indeed help Apple improve their products, you can save battery drain (and your privacy!) by unchecking them all.
Note that "Analytics Data" states that Apple will send "daily diagnostic and usage data", and that the "Data may include location information!"
Note that "Improve Siri and Dictation" allows Apple to store and review the audio of your Siri and Dictation interactions from this device"!

App Store

(occasionally BIG)
Settings. . .App Store

Even if you have unchecked "Background App Refresh under "Settings. . . General, this entry under "App Store" will allow apps to downloads, updates, and "In-app-Content" in the Background!
I am beginning to understand why the first iPhone 15 devices ran hot! There's all kinds of activitity going on inside these devices!
But do note that the first Entry "App Downloads" might be something you actually want if you have downloaded an app and want it to appear on your other Apple devices.

Mail Fetch

This section applies whether you use email regularly or only rarely on your iPhone. Indeed it might apply even more if you use email rarely, since it involves a pretty heavy background process to support an app that is only infrequently used.
For example, I actually use Email on my iPhone only when traveling - and I do very little travelling. Almost all my email activity is conducted on my Windows desktop. Nonetheless I have my email set as described here.
"Push" and "Fetch" are simply terms for retrieving new emails that have arrived to the email server.

If an email server sends a mobile phone new email data from time to time, this is "Push". It is said to use more battery power. This is because the phone has to have a process going all the time to be ready to receive the data whenever the email server decides to send it. One might ask "what about a setup where the email server "wakes up" the phone and sets it up to receive the data?" This is considered a security risk.

"Fetch" means the phone will, at predetermined times, procure any new data the email server might have available.

Either one of these simply means that when you open your email, all new unread messages are already loaded. If neither Push nor Fetch were ocurring in the background, it would simply take a bit longer for Mail to present you with the latest unread messages when you invoke it.

A note about all this:
There is an extraordinary amount of confusion and differences of opinion on all these matters! But the way I see it is simply this:

If you use email infrequently on your iPhone, then setting Fetch to "manual" makes sense because you are eliminating a constantly-invoked background process for something you don't use much.

If you use email frequently on your iPhone, then setting Fetch to "manual" won't affect you: the new email will be fetched every time you invoke Mail.

Settings. . .Mail. . .Accounts. . .Fetch New Data

Here's the Mail section. First of all, make sure "Siri and Search" is OFF. Then Make sure "Notifications" is OFF, although you may want this ON if you use email extensively on the device. Whether or not you use email extensively on the device, it might be well to turn off "Cellular Data". This will reduce battery drain and save you Cellular Data usage. We then select "Accounts" to adjust the "Fetch" settings.		When you select "Accounts", you see this page. Select "Fetch New Data"
		Inside the "Fetch New Data, you can turn "Push" OFF. Then, for the "Fetch" setting, select "Manually".

		But NOTE: If you are on the "Fetch New Data" page (not the "Accounts" page), and you select "Yahoo! mail (or your mail account) at the top of the page, it leads to another page, titled "Fetch Schedule". "Fetch" may still be selected. (Shown on right) If you see this, change it to "Manual"
NOTE:I did make all these changes, and found that when I selected "Mail", the new and unread emails appeared after just a few seconds, and a message appeared on the bottom: "Updated Just Now".

Finding High Battery Drain Apps

While it is not possible (for dubious reasons?) to view the things that processes are doing on an iPhone, you can at least view what they did.
Settings. . .Battery

To do this, go to Settings. . . Battery. When there, you can choose "Last 24 hours" or "Last 10 days". Scroll down, and you will see these stats. These figures show the percentage of the battery charge consumed by each app/process that was used during the period. Since I have been going through "Settings" a lot for this article, you can see that it tops the list.

If you select "Show Activity", the screen changes to the total time that you have used each app/process. I have "Last 10 days" checked.
NOTE: The device displays the screen time (how much you have been viewing/using the process). But it also lets you in on the apps' dirty little secret - the time each app has been doing something in the background!
I must confess, I have never noticed the extra button "Show Activity" before! Maybe it's new.

iCloud Revisited - Synching Photos

As stated in the beginning of the article:

You can use iCloud as a backup, but you must be very careful.

"sync" can be a destructive word!

Why is that?
If you select "Sync Photos with iCloud", this means iCloud is no longer a "Backup" in the sense you might be used to.

If you delete photos on your iPhone, they will also be deleted in iCloud (and any other device that you have synced to iCloud).

If you "unsync" the iPhone at a later date, the process becomes really murky. You may be asked to download them all from iCloud, or delete them from either your phone or iCloud. Further, the behavior depends on whether or not you have set "Optimize iPhone Storage".

As also mentioned above, I transfer all my photos to my Windows PC, usually right after I take the photos. I then delete them. This gives me a big BONUS! The Photos app spends quite a bit of time, computational power, and battery drain to sort/categorize photos by "People", "Places", "Space Aliens" and the like. From what I understand, this cannot be disabled. By offloading my photos regularly, I prevent all this superfluous activity!