I think the author is missing part of the reason it runs through the servers. Along with storing the "read it later" actions, running it through their servers

I think the author is missing part of the reason it runs through the servers. Along with storing the "read it later" actions, running it through their servers allows background checking and push notifications, which isn't possible for 3rd party email services on iOS otherwise (though I agree that a graceful fallback to checking gmail directly would be nice)