At its launch MailShot was built around the Mail system provided by iOS, and required the Mail app to be installed, with at least one email account configured.
In iOS14 Apple have added the ability to set a different email app as your default, so that web links etc. would call an alternate email app, such as Gmail, Outlook, Spark, Yahoo and others. Mailshot now supports sending email to your groups directly through these alternate email apps, instead of Mail.
How to use alternate apps
Set your desired email app as your default (typically from a setting on its own Settings page). Then enable “Allow Alternate Apps” on the Mailshot page, in Settings.
TIP: If you don’t have iOS Mail, MailShot will now attempt to use an alternative email app, irrespective of the setting of that switch.
Limitations and Differences
This feature relies on an internet-standard way of opening email apps, which has some limitations, compared to the old Mail-based system.
You can’t specify which default email account to use, so any “From:” line you set in Mailshot’s settings will be ignored.
You can’t include attachments from a share extension (such as documents, contacts or Photos) through alternate email apps, so Mailshot will offer to send via Mail, if you include attachments.
Note that you need to run the main app after making changes to Mailshot’s Settings, so the share extension can discover the changes.
Soluble Apps 