[quote:3v3o2ju3]Is there another way to keep track of time played across the app being closed?
Yes, I recommend rexrainbow 's TimeAway plugin.
It works with the Local Storage, but saves you all the tedious saving and loading.
This won't work for the total time in the app though, obviously.
[quote:3v3o2ju3]Is there another way to store numbers besides Local Storage
If you want your app/game to work offline and don't want to work with the system time, you will have to work with locally saved files.
Apart from LocalStorage, there is also the possibility of saving, loading and parsing files with NW.js & AJAX.
This will be more complicated, but will also give you more freedom when it comes to the workflow.
[quote:3v3o2ju3]but say they uninstall and then re-install the game, the Key is missing
That's the way, LocalStorage works. The keys/values saved by LocalStorage are part of the app, so they get deleted as well if you delete the app.
If you don't want to work with online servers and you are not on mobile, you could use the registry, but apart from that, I don't know about any other ways of saving and keeping values even when the app is reinstalled.
(That's just me though, there might be others out there who know better)
[quote:3v3o2ju3]Like where its supposed to update the global variable with the Key value it says NaN
As mentioned above, when uninstalling the app on mobile, the LocalStorage keys will be deleted since they are stored in the same location as the app.
NaN in connection with LocalStorage will appear when there is no data available. (Or if you try to combine strings and numbers, but this doesn't seem to be the case here)