The Tiki newsletter feature allows you to send a newsletter via email to a list of subscribers. The email can be sent in HTML format, plain text format, or both. Other newsletter features include:
user controlled subscribe/unsubscribe
Admin can restrict subscription to the users email address of record, or allow any address to be used.
Admin controlled subscribe/unsubscribe
email address validation
a 'reply to' email address can be set that is different from the system 'send from' address
from Tiki 15.1 (and backported to 12.7) a 'send from' address, that is different to the system 'send from', can be set for an individual newsletter sending
from Tiki15 (and backported to Tiki 12.5) counters have been added when sending Newsletters, which is useful when sending newsletters with a large subscriber list - it is also particularly useful when the option to 'throttle' the newsletter send rate is being used which is an option that may have to be used to avoid the sending system being 'designated' as a spammer and being blocked by receiving mail servers
include unsubscribe instructions in the newsletter
granular object permissions for viewing, sending, etc
Groups can be subscribed to newsletters (including embedded groups)
Since Tiki6 you can now also 'subscribe' a Wiki page so that its contents, whatever it is at the time, can be used to define emails to which an individual Newsletter Edition is sent.
From Tiki 6.1 the quantity of 'styling' information embedded within an HTML formatted newsletter can be controlled by the use of a dedicated css file.
Since Tiki6, you can automatically send newsletters with a cron/batch job based on some wiki page template with plugins (upcoming events, last posts, new items, ...).