Sorry, I never used S Memo (heck, I can't even find it on my phone!).
I'd recommend Keep:
http://market.android.com/details?id=com.google.android.keep - it syncs to the cloud, so even if your phone gets destroyed you still have access to the content.
Edit: looks like it's only available as a widget - that's why I didn't see it.
Edit 2: there seem to be options to Sync (with Google Docs & Evernote), to Export, to Backup to SD card and even to Auto Sync with your Samsung account - I guess you didn't do any of those things?
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