currentTime, upTime, clocks, timers and the bugs nobody talks about

Ah the classic System.currentTimeMillis and the SystemClock.upTimeMillis dilemma. What are they for and why can’t I just have one clock to rule them all?

Which one is affected by time zones and which one is affected by system sleep?


See how we make using clocks painless at Sentry and the journey we took to get us there. We’ll cover when to use which clock in Android/Java/Kotlin. And how to set up a proper abstraction so humans and LLMs do the right thing™ in your codebase.

Trigger warning: time zones are discussed