You can use tethering on Verizon without their app also, there are apps that turn on tethering without a Verizon tethering plan on an unrooted phone, on a rooted phone it's built in. I had a Verizon Galaxy Nexus before my Nexus 5 (on AT&T). I used one of those apps early on, before I rooted my phone, and it worked fine. The FCC fined Verizon for trying to block the tethering apps because as part of their spectrum agreement they had to allow tethering. However Verizon obscured the fact that you didn't need their permission to tether. Their tethering plan gave you an extra gigabyte in exchange for the $20 a month so technically they weren't violating the FCC rule.
The Nexus 5 is a true Nexus device without carrier interference (unlike the Galaxy Nexus) so the hotspot feature is front and center, it's on Settings under More.. There are things that look like apps that will get you to the Settings section, but they are really just links.