Literally every time you see a startup release a product that seems trivial it's because that's not the full story. You're judging without complete information. For example, the public face might be a simple Mac calendar widget, but that could be the gateway to calendar sharing, native office apps, meeting booking, event management, ticket sales, corporate flight sales etc. Building an audience with a cheap tool that…
Indeed the founder says: >We’ve only solved a small part of a bigger problem. The SaaS platforms we use for work don't work well together. It shouldn’t take cycling through ten different apps and Chrome tabs to stay on top of everything. >We’re now looking to bring Slack and GitHub into a unified notification inbox in the menu bar. We want to better organize everything you use as we’ve done with Google Calendar.
Maybe I’m too cynical but I remember back in the days of multiple IM services, MSN Messenger, Yahoo, AIM, etc. One company would try to implement interop with another, only to be shut out a few days later.
I’d posit that if they are even remotely successful at building a unified notification inbox they’ll get their access shut off very quickly. These companies don't want to share.