So, I ended up renting a HUI vehicle today. I just needed a vehicle from 10am to 5pm to run around the island with. It was actually a surprisingly simple thing to do. Got the car at the Waikiki Beachcomber location and unlocked it with the app. It was strange to us an app as a key fob and start the car but got used to it. I am assuming there is some way that it downloads the key to the app and that data service is not required or it would be scary. There was an octopus style charging cable provided and that was appreciated as I did not think to bring my own cable. As mentioned, a dead phone appears that you aren't able to start the car.

I did like the ability to just turn it in without dealing with people and also no need to fuel up. I do wish I read the FAQ's a little more before renting to familiarize myself with their policies in case I screwed up anything by accident but luckily I didn't. https://www.drivehui.com/faqs/

I paid about $96 all in for my rental which seemed reasonable compared to quotes I was getting for Hertz without even considering gas etc.