If your phone lost then don't worry with samsung. You are the true owner if the theft don't give your phone remember you'll have two option
1. Google find my device ( locate, lock phone, remove data or reset)
2. Samsung find device( locate, lock phone, remove data, factory reset, ring phone, and retrieve call and messages data)
If your phone not connected with internet just lodge lock screen option or retrieve messages call log option. When the theft comes online just for a seconds your phone will lock to new password which you set on Samsung find my device
(Useful Tip: instead of remove account or factory reset option you should choose lock screen option because with the help your phone will not unlock till pin or password enter if the theft reset your phone from recovery menu on startup or any other way google will block access during first boot setup. It will ask your old google account and password. So if he not give back your phone . Then it will also unusable for that person. So thanks to both android security and samsung security)
Keep your phone always update specially security updates. And stay not to worry Smiling_Face
Always turn on option ask password before startup. By turning on this option your phone data will encrypted while device off. So not to worry nobody can access any of way your data. Because internal memory chip encrypted while off. For more security encrypt your sd card also.
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