How to manage mobile data on LG G4?
You can select whether to enable or disable auto-sync and select options for how to interact with mobile hotspots.
Note: Some Settings, Menus, or Icons may differ from that of your device depending on your software version and wireless
service provider.
1. From the Home screen, tap the Apps
> Settings
> Networks tab > Mobile data or Data Manager 
2. Tap the Mobile data switch
to enable mobile data.
3. Checkmark Limit mobile data usage
which allows you to set a limit for mobile data usage on the device.
Once the limit is reached, your mobile data connection is disabled and you will receive a notification.
4. Tap the drop down box Data usage cycle and tap Change cycle. Select the Usage cycle reset date, or date that the usage cycle
will repeat from each month.
5. In Mobile data you can adjust the following:

② Upper limit slider bar - Use this to set when the mobile data connection is disabled. Limit mobile data usage option must
be enabled to adjust this slider bar.
③ Lower warning slider bar - Use this to set the usage warning level. When the device reaches this level, you will see a usage
warning.
6. Tap an application to get a detailed usage view during the same Data usage cycle as well as additional usage information
and options as follows.
① Detailed usage graph.
② Foreground and Background - Shows usage stats within the period.
③ Restrict background data - when checkmarked
this will restrict the application from using mobile data in the background.
7. Tap the Menu key
and choose from the following:
① Restrict background data - when checkmarked
this will restrict applications from using mobile data in the background.
② Show Wi-Fi usage - allows you to see the Wi-Fi usage on a tab, similar to mobile data.
③ Mobile hotspots - helps you to limit mobile data usage when connected to specific Wi-Fi networks.
Checkmark
the Wi-Fi networks you would like to restrict from using background data. Apps may also warn before using
these networks for large downloads.