There's also a few mentions of RTC and such in the documentation on the Wiki. If it is not used in the same way as the name 'RTC' implies, that is a little confusing - they should stop calling it an RTC. Or at least clarify the usage.
So, correct me if I'm wrong: there is not an internal RTC comparable to the DSxxxx ICs, BUT there IS an internal clock that shows time from power-on. I got that.
How accurate is that internal clock? So I can estimate how often to try to update the time via Wifi.
I would like to reduce the external parts count, but I guess I will use a DSxxxx RTC if it comes down to that.