When comparing CauseOs vs Nitronews, the Slant community recommends CauseOs for most people. In the question“What are the best services for sending newsletter/marketing emails?” CauseOs is ranked 8th while Nitronews is ranked 12th.
Ranked in these QuestionsQuestion Ranking
Pro Cheaper than mailchimp
Pro Great support
These guys will do anything for your organization.
Pro Detailed analytics
Pro Free plan
With options of monthly or pre-paid plans.
Pro Customer support via phone
Pro Simple and Advanced mail editors
You can choose to use a Beefree or CKEditor to edit your messages.
Pro Tutorial for beginners until the first sent mail
The company is in early stages of development.
Con Brazillian Portuguese only
As the time of writing(30/08/2016), the only language is pt-BR. Even though the support answers in English if needed.