I had a great experience with https://www.printexperience.com for my custom USB sticks.

Firefox "Focus" browser does the trick for ad-blocking and erasing history on iOS. No tab support though.

If you install Firefox Focus, you can use its as blocking in all browsers. I use it in regular Safari. I can’t remember if this happens by default after installing Focus, but if you go to Settings - Safari - Content Blockers, you can enable/disable the Firefox Focus blocker for regular Safari.

Last time I heard that was the Maemo OS codename before Diablo

The Nokia N810 was the best. Regarding the keyboard, it helped if wrapped your hand around the kickstand. Great for writing shell scripts while waiting at the DMV