I give in on the 'vanishing notes' thing. If it has not caught you out yet, it will if you use it frequently.
I get that it stores under certain 'accounts', and looked through there in vain for one pages-long note that spouse created. I scoffed at the notion the data could simply 'disappear'.
Well, then I did a multipage length document (guessing, it does not have pages as such of course) and as I opened it, and poised my fingers over the bluetooth keyboard to start tapping, I glanced up and indeed right before my eyes, the text vanished.
The app was open about two seconds and all that happened was the text vanished on the main area, simultaneously the title(first line of the document) disappeared on the left hand side column, and the 3 icons on the top right went down to just one being lit up or whatever.
So, it's duff. Never had this problem with iOS 6, but within maybe 3 weeks of iOS 7.1, it has happened twice in a week in the 'Notes' app.
I have replaced it at the front screen of stuff on my ipad 4 retina, with another one for £1.49 or free with ads, and sent the icon for 'Notes' to the last screen full of apps I never go to much.
Any tips, welcome, but I call it a fatal glitch until someone can either explain or cure it.
Best regards for now.
iPad (4th gen) Wi-Fi + Cellular (MM), iOS 7.1, Loads of space free on ipad, 30Gb.