I believe it updates every 5 days, but sometimes I've seen 30 seconds drift in the sleep clock (and in my own Playtime app) in less than 2 days. The clock could potentially get several minutes off before correcting itself.
Checking daily would keep the clock on track!
(But if it only checks when asleep, it would be great if it could also check while an app is running!)
Alternatively, if an app could force a time lookup using the SDK, my clock app could handle this itself. (But that wouldn't help the built-in sleep clock.)
They do seem to drift a lot! But they can also correct that, so maybe simply checking the network time once or twice a day would do the trick.
I left mine with no app running, just the standard sleep clock, and watched it drift over 30 seconds in a day. Then it fixed itself! It happened when a sideloaded game update was downloaded. That seems to be one of the time-check triggers?
Yet the Monday season downloads did NOT correct the clock, so it may have been coincidence.
it polls the server every 6 hours to check for new games, might as well start building API for it to expect multiple data types in a single response. Including the time, maybe notifications (ie: your highscore was beat in game X, you could clone Vita's "near" service/3DS's streetpass so games could send items to people on your friend's list)
