Let me try to beak this down for you. Launch the Notes app on your iOS device and tap the button in the top left corner until you're on the Accounts page.
On the Accounts page you should have several options - This is where you choose the location that your Notes will be saved.
'On this iPhone' will save the Notes to the iPhone the Notes can only be deleted from that iPhone.
'iCloud' may be present if you have set iCloud to sync Notes so you can share them with other iOS devices -These Notes can be deleted from any iOS device set up to sync Notes with that iCloud account.
'Yahoo' or 'Gmail' (if you have both) will save the Notes to the email account - Here's the funny thing about saving Notes to the email account
If you delete a note from the iOS device it will stay in your email as that is where it was saved.
If you delete the note from the Email server via the Mail app of in Safari on the Mail providers site it also deletes the note from the iOS device. This would be like deleting a saved copy of any document on a computer.
My thought is your iOS device is set to save Notes to your Email account and you inadvertently deleted the notes from your device. I don't know for sure but good it's a good thing they where still saved to your email. For your friend I would have her check her email account for the missing notes. Hopefully she can recover them. Personally I would use 'On this iPhone' or 'iCloud' to save the Notes, the email option is to risky as I clean my Mail out on a regular.
I've had an iphone for years and never had a problem with my notes disappearing before. But recently I noticed a few notes were gone so I just assumed I'd deleted them. But today all my notes were gone! I hoped I could find a solution here but I guess no one has it.
I was able to get my notes back on my iphone since they are connected to my yahoo account. I emailed them to myself then copied and pasted them in the notes again. Of course, I did the same yesterday when I noticed some were missing and they just disappeared again. Guess I'll have to start using another notes program.
Actually,you can recover lost data from broken iPhone or even lost the iDevice with a professional iPhone data recovery, this iPhone data recovery tool-- iPubsoft iPhone Backup Extractor can help you restore any lost data from iPhone 5S/5/4S/4/3GS,you can use the iPhone data recovery program to recover iPhone photos, videos, contacts, SMS, calendar, notes and call history, etc. in two recovery mode.Please keep reading the detailed solution to recover lost data from iPhone in two ways.
Two ways to restore lost data on iPhone with iPhone data recovery software
Mode 1: Recover Lost Data from iPhone Directly
Tips: This recovery mode allows you find the backup file and preview the contacts, photos, SMS, videos, calendar, notes and call history in details, it supports recover lost data from iPhone 5, iPhone 4S, iPhone 4, iPhone 3GS or previous versions.
Step 1:Connect your iPhone to the computer and scan
Step 2: Preview and selectively recover iPhone data
When the scan finishes, all found data are displayed in categories, like camera roll, photo stream, photo library, contacts, messages, message attachments, call history, calendar, notes, reminders, voice memos and safari bookmark. You can preview full contents of all of them one by one.
Step 3: Start to recover all lost data from iPhone
Mode 2: Recover Previous Data from iTunes Backup
If you have backed them up with iTunes and iCloud before, then you can get them back from the backups in both iTunes and iCloud. But if haven't, you can use iOS data recovery to scan and preview the lost or deleted notes directly from your iDevice. You can also recover the specific file that you want to retrieve.