Walgreen's IDNow test is a Nucleic Acid Amplification Test, NAAT. If you look at the CDC website, you'll see NAAT's as being the "Gold Standard" for Covid testing. PCR testing is good, too - it's just more well known because it was put into use first. The IDNow test isn't specifically listed on the EHAS site, so some people on social media are having hissy fits over its validity, despite several emails posted online from EHAS that they accept it and tens of thousands of people having used it successfully. There have been some reports of gate agents holding up people over this test, mainly all Delta, but everyone has been able to get someone else involved who knew better.

You will have NO problem using it for your Pre-Approval letter from EHAS. They treat IDNow the same as a PCR test as far as time limits. We used the IDNow test in June, as did our entire family of eight, and just about everyone we met during our month there used Walgreen's IDNow as well. As far as the airline gate agents, there were some posts a while back on Facebook like I wrote above but given their training (esp Delta) since then, it would be amazing if you still had that problem now.

When you travel to other islands, you'll find that the NAAT tests like the IDNow are the preferred. Check Hawaii's and the USVI's admission guidelines, for instance.