Remove Galexy edge s7 system update notification

Almost all options require root.

1. The most clean and safe option is to edit build.prop file. Use any file manager which provides access to root filesystem.
   You can learn about build.prop here.

   
   
   

   The setting which is of interest to us is ro.build.version.release.

ro.build.id=JSS15J
ro.build.display.id=JSS15J.I9505XXUEML1

ro.build.version.incremental=I9505XXUEML1
ro.build.version.sdk=18

ro.build.version.codename=REL
ro.build.version.release=4.3

ro.build.date=Tue Dec 10 14:28:08 KST 2013

ro.build.date.utc=1386653288
ro.build.type=user ro.build.user=se.infra

ro.build.host=R0210-09
ro.build.tags=release-keys

ro.product.model=GT-I9505
ro.product.brand=samsung

ro.product.name=jfltexx
ro.product.device=jflte

ro.product.board=MSM8960
ro.product.cpu.abi=armeabi-v7a

ro.product.cpu.abi2=armeabi
ro.product.manufacturer=samsung

Just change it to 7.0 and Android will be fooled and think that you already on Nougat. For 100% fooling you can also change ro.build.id, ro.build.display.id and ro.build.version.incremental properties to NRD90M, NRD90M.G955FXXU1AQDG and G955FXXU1AQDG values correspondingly (aka Nougat values).

Reboot after the applying changes.

2. If you lack root, you still can try Titanium Backup. But this way can also require root though.