LG Optimus L4 II Guide De L'utilisateur page 382

Phone software update
NOTE: Your personal data from internal phone storage—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.
NOTE: This feature depends on your network service provider, region and
country.
82