LG G4 Stylus Guide De L'utilisateur page 477

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 backup your personal data before
updating your phone's software. LG does not take responsibility for any
loss of personal data.
This feature depends on your network service provider, region and country.
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Phone software update