The Fastmail web client is far better than using IMAP/Apple Mail client. But the iOS Fastmail app is really good, so I use that on the phone. Fastmail works w

The Fastmail web client is far better than using IMAP/Apple Mail client. But the iOS Fastmail app is really good, so I use that on the phone. Fastmail works well for small business (at least). The limits are high, and there are a lot of features that Gmail doesn’t have. I don’t use the FM calendar, so I can’t speak to that. I’ve found their file storage very helpful in moving data between disparate platforms. You can even set up small static websites.