Short and simple: buy Scribe and thereafter you can type something on your Mac and it'll just be there on your iPhone or iPad when you turn around. Scribe is free in iOS and US$2.99 for Mac.
Slightly longer and less simple: isn't that what iCloud is supposed to do? Yes, kinda, and it is definitely true that you can and that I do use Evernote for exactly this. I also use Pages for it. And Numbers. But Scribe is meant to be like the clipboard: just as quickly and effortlessly that you copy something and paste it somewhere else, that's Scribe. It's just that you're copying it on your Mac and pasting it on your iOS device.