I have recently installed Norton Mobile Security, currently version 3.15.0.3134. I am finding the performance of the tablet has dropped as Norton always seems to be running scans. In the app settings I have left the "Scheduled scans" setting as Weekly. However, if I look in the activity log I see scans at least once a day. The log usually shows "Malware scan ran due to LiveUpdate". In the activity log I see between 10 and 15 entries for each day (mainly LiveUpdate, and mostly "already the latest version"). So far I used Norton on the desktop and there I see around 13 quick scans in a month. I do not download new apps that much (but do get regular updates), always from the Google Playstore. I had the impression that websites were checked when visited and not after the fact in a scan. Should I be changing some of the settings to reach a bit better balance?.
LiveUpdate is limited, and does not really concern me. I notice when I pick up the tablet and log in with a pin code that it sometimes takes about 5 to 10 seconds before the asterisks appear. Also some apps requiring internet time out. Yes, if I start them again they work.
Thanks for the comment about when an update and scan takes place. For me that seems a bit excessive, especially when only using trusted networks. I do realise that with other networks there could be more risk. I had not found these comments in the forum. Is there a way around that? I know... rather safe than sorry, but on my desktop Norton works just like I want it, always there but almost never obtrusive. The tablet and smartphone have not reached that stage yet.
The amount of data moved in a Live Update should be limited and even though this frequent checking may not be what you would choose, I would be very surprised if it impacts other than very briefly on your tablet. You could try uninstalling and see if the performance improved noticeably. I would be surprised but interested if it did.
As for the frequency and the use of Google Play...well Norton checks apps each time they are updated as well as when they are first installed and it warns against issues such as data and battery usage which Google Play does not worry about. And again it provides an extra level of checking even if Google check first. So not all bad... maybe...
This has been brought up before. What Norton has said is that LiveUpdate will run every time an internet connection is established. Wifi or Cell Data. So as you move from a wifi connection to a cell connection, Liveupdate will run. And by default, a scan will run after LiveUpdate finds new malware definitions. This scan just ensures that you device is safe from whatever is covered in the new definitions.