Web server and external clock source for counter on Photon

Newb here. I’m considering the Photon for a basic clock. To achieve the requisite accuracy I’d like to drive a h/w counter with an external TCXO while the Photon is asleep, then wake it up with an overflow interrupt every minute, have it perform its clock stuff, then go back to sleep. Is this possible? Any idea what the accuracy of the 32.768 kHz xtal is that’s on the board? Could that be used instead?

I’d also like to create a web server on the Photon’s own local network that will throw up a configuration page to any browser that accesses it (e.g. from a phone). I found a way to do this using mDNS and Webduino, but the tutorial is three years old. Any better ways now?

Thanks for any tips.

Not sure why you'd want that. The Photon features a RTC (realtime clock) that can wake the device after a time you set when sending it to sleep.
The drift of that RTC over one minute is negligible.

That solution was pretty good back then and still is.

Thanks. I’ll look into the RTC.