Not the solution I was looking for but . . .
In the upper-right of the GMail app is a small, circular, icon with my initial X
displayed as a white letter X on a purple-violet circle background.
Tapping the X icon showed my secondary personal email accounts as well
as my wife's.
From there tapping Manage accounts on this device showed a full list
of the 4 gmail accounts I may have added to my iPhone's GMail app at some
time in thelong distant & forgotten past, though I suspect these appeared
through some kind of Google wizardry so they can track me, everywhere?
One account had its slider turned to the "off" position - to the left - while the
other 3 are each "on" (including my wife's gmail account) with their sliders
to the right.
I turned her's "off" and tested: the GMail app showed my email in the "From" field.
Turning her's back "on" confirmed: now her gmail account was in the "From" field.
Is this because GMail defaults to an alphabetical listing of email accounts?
My wife's email address starts with a "a" and mine with a "b" .
All my other email accounts start with either a number, or letters that come after "b".
If this is the way the GMail app behaves then thats pretty shoddy.
One should have the option to specify a default account.
Checking further . . .
I went to Settings > Passwords & Accounts and added my wife's gmail account.
Then I went to Photos, selected one to share, chose Mail:
Mail defaulted "From" to my email address. Tapping "From" pulled up a scroll section
from which I could choose any email account for the "From" field including my wife's.
The point is: the Mail app remembered the most recent email account used
in the "From" field whereas the GMail app used the email account with the
highest alphabetical sorting of all email accounts in the list.
Or . . . does the Mail app simply default to the iClould account of the device which,
on my iPhone, is me?
The Mail app allows an account to be turned on or off by sliding the Mail slider
of an account to the left in Passwords & Accounts.
However, the Mail app also has a Calendars slider to chose on or off.
When I tried to turn off the Calendar slider a popup warned me that if I continued
ALL GMail calendars would be removed from my iPhone.
I chose to leave C alendar on for Mail at least until I get around to moving away
from Google entirely. This is not so easy to do. There are so many other accounts
that have my gmailaddress linked. It will be several days, perhaps even weeks,
to plow through all the various online accounts I use and change their email addresses.
Quit a job.
From within the GMail app (clicking the account icon in the upper-right of the screen)
the GMail app allows one to put an account to "sleep" by moving its slider to the left.
Seems pretty simple, but I do not like not having the option to specify a primary
email account for the GMail app to default to when sending/replying to emails.
If anyone has anything to add please comment!
Thanks!
