(e) (1) “Covered application store” means a publicly available internet website, software application, online service, or platform that distributes and facilitates the download of applications from third-party developers to users of a computer, a mobile device, or any other general purpose computing that can access a covered application store or can download an application.
No, you cannot. If you're distributing applications from third-party developers, you're covered. Also, just to head off the obvious: No, even if you're a first-party developer you're not off the hook because the bill still requires you to handle age signals.
In any case, no, it does not move "click here if you're over 18" to account creation with respect to an app or service, but to account creation with respect to a device. So mommy/daddy buys you a new iPhone 666 Buttplug (or whatever) and gets prompted how old you are and they set your age accordingly. If they're dumb enough to let their kid set up their device themselves that's a failure on their part and the rest of society shouldn't be made to pay for it. Likewise, expecting there to be some legal remedy that can stop a kid from grabbing an adult's device with an account already on it is asinine ... that's what passwords and keys are for.
Ultimately I wish parents would actually be parents to their children instead of expecting the rest of society to nerf itself... failing that, I'm going to start developing a lot of very pointed opinions about what you and your children are able to do on my internet, and you definitely won't like it.