Take current time and in 99.99999999999999% of cases it’s the same as the server. Servers don’t usually drift unless something is very broken, at which point it doesn’t really matter 

 Are all clients and relays expressing times in UTC? 

 It’ll be in ISO or Unix epoch, you can take it from there since TZ is either explicit or UTC by default 

 Yep that's right. Thanks! 

 Clarification: I'm sending a REQ with a `#d` set of app IDs to check for updates.

But I can't include one `since` for each app ID in one query, so I have two options: 
 - use the oldest `created_at` of the app ID set - but if one of the apps is quite old, I reap almost no caching benefit
 - send one filter per app - this would work well, but I could have potentially 100s of apps to check which translates into 100s of backend requests for one check

If the relay sent a timestamp, I could use that as the `since` for the next request. The only drawback is it wouldn't catch any back-dated apps, but that is uncommon. 

 There is no discrepancy. Most apps need to be in sync with NTP just to use the regular web. It works quite well for amethyst.  

 Nice. Are all created_at supposed to be in UTC? 

 No need to convert timezones. Your unix Timestamp and the servers Timestamp are the same regardless where you are. 

 Oh, right, unix timestamps are always UTC. Thanks man! 

 android and linux use UTC in their real time clocks but windows uses the local time and if that's wrong it is wrong

windows is wrong, the internet is international