I posted a community document with a basic integration using Insert from URL and JSON functions. Has an API key and a bogus mail account setup to test sending mail with plain text, formatted text or html. Attachments are currently limits to JPEG, PNG, PDF, XLS/XLSX and FMP12. Fits iPhone 6s screen size and larger.
I decided to pre-generate recipient and attachment JSON as part of the related record as it made assembling the arrays easier by simply using the List( ) function. Further updates with more SendGrid features in the future.
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