We'd known Gmail was changing their rules for API integrations at some point this year, but this was the day we found out it was months sooner than we'd expected. The new rules required that you get a 3rd party security review, quoted between $15,000 and $75,000. But that didn't even count whether or not you'd get approved! As indiehackers we weren't able or willing to put up that kind of money, and we weren't ready to launch yet either.
This is when we started planning a new strategy... what is Arrows if we can't use a Gmail mail integration??