You can't actually get the savings rate, because it isn't currently a running business or bank. It is an early stage startup (i.e., a business pitch), they are trying to collect email addresses for a wait list. This is a very typical strategy for dot-com startups now a days, and honestly I've seen pages like this given as an assignment for students where they are asked to build such a page to show they learned something about entrepreneurship/marketing/etc. It is hard to get in trouble for making unsubstantiated claims when you aren't actually selling anything.
The tactic works like this: make a website with a full sales pitch on your product/service/business, and invite people to "get on the wait list" or "apply for the beta test" or "get early access", etc. There is often no product whatsoever in existence, beyond the web page built to collect your email address. You can get a hint of this on this company website by the fact there is an image showing buttons to get it on the Google Play Store and on the App Store. What happens when you click there? Nothing, its just a screenshot of what such a button would look like. If there was an app, it would likely just be a mobile web form inviting you to sign up for the wait list too.
Everything they have to say about how they might possibly achieve what they claim is put in an FAQ on the web page, but honestly it doesn't matter (they claim they will just deposit your money for you in many different bank accounts so that collectively the insurance is up to $100M - they don't have to show they can actually do that, which they probably can't, it is just a website). If you do some looking around one of the co-founders claim this particular company started literally last month (January 2019).
There are actually a number of these going around, so you might ask "why do they bother with all this?" The business strategy is to collect a big list of "potential customers" they can tout to venture capitalists and potential investors in an attempt to get people to give them money. If they collect enough millions, they may try to build an actual product and operating company, and then they will just revise their promises until they make sense - or they will use investment capital to pay temporarily high returns and hope they keep raising money faster than they lose it.
This of course is also not the only attempt at offering high-yield savings accounts around 3% or more. For instance, the more established company Robinhood recently stirred quite a bit of debate for their high interest savings offering. And as a cautionary tale, if Robinhood can't just split up money into a bunch of FDIC insured banks and offer 100M insurance per account just like that, and instead must rely on non-FDIC protection, chances are that a web-page-only startup is going to find it hard to deliver on their promise even if people give them piles of investment money to play with.
Bottom line? Talk is cheap, especially when people are promising you easy, safe, guaranteed returns on your money that are higher than any normally available alternative. A fool and their money are soon parted - don't let it happen to you.