The problem is bulk ordering tests - you need a massive investment (about 750k for minimal order size of 100k tests), which he's been trying to find some philanthropic money for.
Those finger prick tests are convenient, but they only show results if your body is already producing antibodies. The really good test is an RT-PCR or RT-LAMP test, which uses a pretty invasive swab technique. It's pretty unpleasant.
Colormetric RT-LAMP is the right method for that startup (probably) because you can deploy it with pretty few resources and get rapid tests. However, it can be finicky, and isn't approved by the FDA AFAIK.
What I do not hear people talking about is this: Getting tested once is not enough. If you do not have COVID-19 today, it doesn't mean you are not going to have it tomorrow. The only test that can tell you that is an antibody test. Also, we don't even know yet (for sure, anyway) if people can be re-infected.
Additionally, the same (or another) startup could make it easy for companies to pay to allow customers to be tested with a 15 minute test. I would not mind waiting outside a restauraunt or supermarket for 15 minutes while my test is run, if it means that I could enter knowing everyone else in the building is uninfected.
I imagine you would supply each business with one or more testing machines, test kits, and some number of technicians to operate the tests and test machines correctly.
The hard part is probably getting test machines/test kits while supplies are limited.