Classical automation through SAAS mostly done through

• Zapier (SAAS)
• IFTTT (SAAS)
• Power Automate (Microsoft)
• Node Red (open source)

Since the advent of AI, there is a shift in focus, where these seem to be more popular:

• Make.com (SAAS)
• n8n (SAAS and selfhosted)

Furthermore there are also AI tooling hub now which have gui’s for all kinds of AI supported tools:
In particular Dumpings.ai (SAAS)integrates closely with make.com

Automation fully with code

• trigger.dev