(You can also read more on our open source and standards work at https://www.fastmail.com/company/open-source/)
Just so you know, the next-best provider is Proton and they're in HEAVY growth mode at the moment. Their UI is strewn with upsell widgets.
* Despite a buyout by Opera, the company's employees bought it back in 2013. This indicates passion.
* They're privately held, so they don't have to chase quarterly earnings reports; they can focus on the product instead of the stock price.
* They've been operating in the email domain for 25 years, and their other products (TopicBox, POBox) are in the same realm technically. This isn't a company randomly throwing ideas at the wall to make money.
* They charge customers for their product, so they are not looking for a revenue stream, they already have one.
I'm also highly vigilant for companies that will screw me, but Fastmail is way at one end of my risk spectrum because of the above points. I would be astonished if they would risk alienating their core audience by shifting focus away from a good email service...after all, that's their core competency.
I use Fastmail because of the excellent mail service, customer support, sieve rules to keep my inbox manageable, and because of the little details like WebDAV that I have unexpectedly found useful for things like syncing browser bookmarks. I pay for Fastmail because it has been excellent, not because I’m captive.
This app signals to me that there may be a change coming in our relationship. One in which you may start to neglect IMAP or make it harder for me to choose my own mail client. It tells me that Fastmail might be pivoting into “growth” and treating me like a “user” rather than a paying customer. It won’t surprise me, and I can’t really say I’d be mad. Most companies get to that point. There’s probably a lot more money to be made from vendor lock-in than happy, $50 per year customers. As for me and mine, I will switch to the next small-to-medium-sized mail provider the second I get a sense that this is the direction.