Enis Younsi has sent in this video of a demo Apple Watch in the Apple Store. It shows the watch going from fully off to booted to the clock face, which takes just over a minute. Although it’s not really fair to make such comparisons, due to the differences in the software, modern iPhones take about 30 seconds to launch to the lock screen.
The S1 is currently expected to be similar to an A5 chip. Even iPhone’s powered by the A5 chip did not take this long to start up however. Until the Apple Watch is released, it will be impossible to explain the discrepancy. It is very likely that optimizations for better battery life are the culprit, however.
It’s also unclear how ‘custom’ the Apple Watch demo units in those acrylic cases are. This may affect startup time, although from inspection, they seem near identical to what will ship. Users will be able to test all of this stuff out from Friday, when Apple will start delivering devices to customers.