What tools do marketers have to alert their customers?

Question

Marketing

I am looking for convenient multi-channel or single-channel SAAS for audience notification, posting, distribution of advertisements, etc.
Are there any on the market?
For example, a service where you can immediately submit ads in one interface to Google, Yandex, VKontakte, Facebook, etc.
Types of advertising aimed at informing your audience:

1. Groups in social networks (own subscribers)
   
2. E-mail newsletter
   
3. SMS mailing (+viber, whatsapp)
   
4. web push notifications in the browser on the site
   
5. retargeting Yandex.Direct / Google.Adwords / social networks
   

Types of announcements (messages) by channels:

1. Posts (pictures, video, text, website link)
   
2. A letter designed in a corporate style (simply informational, or with a call to action)
   
3. Text information in SMS to inform your subscribers about promotions or events, in viber / whatsapp you can add a photo of a product / service to the text + a link to the site
   
4. a small text notification to the subscriber in the browser
   
5. displaying an advertisement on the sites of advertising networks of the audience that was on our site
   

What are the SAAS services that can solve these problems? You can even not in one interface, but in different ones.