I thought people would maybe find it useful to see a comparison of these two ostensibly similar products. Not just simply integration tools, they can be used to build logic both within as well as between online services.

• Zapier probably the market leader in this space with integrations to over 1,000 other apps and platforms
  
• Simple User Interface
  
• Excellent tools for converting formats, parsing emails, saving data for consolidated emails etc. New Paths feature adds branching logic (If Else)
  
• Push Zaps can be triggered from Chrome Extension
  

• Integromat is a newer entrant to the space – and has more logic capabilities including looping, combining records etc
  
• Better handling of multiple records within a single process including the ability to aggregate data from them (looping in other words)
  
• Can be really useful for converting data and other complex processes
• For database platforms like Knack and Airtable which don't have their own database language, Integromat can become that missing language
  
• Mobile app can trigger Scenarios from events on your mobile device
• Beautiful user interface
  

Summary

Both of these tools are Incredible and I use them both on behalf of clients…

• Zapier has more integrations already in place – but Integromat also has a lot!
  

But

• Integromat includes ALL features at all license levels (though support varies) and so can be much more cost effective for some users
• Extended logic capabilities in Integromat means it can be seen as a 'language' for platforms without one built in

I hope people find this summary useful - and look forward to any comments or questions people may have!