LG Optimus F6 Guide De L'utilisateur page 341

NOTE: Your personal data—including information about your Google account
and any other accounts, your system/application data and settings, any
downloaded applications and your DRM licence —might be lost in the process
of updating your phone's software. Therefore, LG recommends that you back
up your personal data before updating your phone's software. LG does not
take responsibility for any loss of personal data.
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