Playerpref Saving Lag

Hello everybody.
Theoretical question here: say I have one resource, called x, and every second y, a given value, is added to x. So I could have 20 apples and in one second get 2 more. Now, I want to save x, and I am saving it with a playerpref. I am worried that having

void Update ()
{
PlayerPrefs.Save ();
}

Is to heavy a strain on a mobile devices’s capacity. So my question: could I save playerprefs in the aforementioned method, or should I find a different way. If I should do something else, any suggestions. I am working with numbers in the high thousands, and in c#, if that helps. Thank you for your response.

Well, why do you want to call Save every frame? That doesn’t make much practical sense. As long as your game runs you usually don’t call it at all. If you worried about the game could be terminated midgame, why don’t you call Save every 5 seconds. So the worst that could happen is that the user looses his last 5 seconds.

But seriously, if a user is playing a game and suddenly terminates it immediately as fast as he can, i don’t think he deserves that his score is saved at all ^^. If an app is terminated “gracefully” Unity should save the playerprefs automatically. You can also put a call in OnApplicationPause / OnApplicationQuit. Unless your game crashes OnApplicationPause should be called on all platforms as soon as you switch to another application.