The new APK for the clock app from the Android M Developer Preview doesn't look very different from the one you'll find in Lollipop - most of the functions (alarms, world clock, timer, and countdown) are in the same place and operate in the same way. But there's one tiny change that a small amount of users will be extremely happy to see. The Clock app can now "start" your week on Saturday, Sunday, or Monday.
This is one of those little formatting questions that has never really been properly resolved by society. Most western calendars "start" the week on Sunday, but a majority of people with what you might call a normal job go to work on Monday and consider Sunday the "end" of their week. Now you can select the formatting option that makes the most sense to you.
Well, sort of. Unless you practice a religion with a holy day that's not on Saturday or Sunday, or you work at a 24-hour business with a starting day sometime in the middle of the week, or you're a military or medical worker with shifts that would drive a 9-5 person insane. Hey, at least Google's trying. The newly-formatted clock app is available in the developer preview, but if you'd like to try it out on a current Android device, it seems to be working fine on Lollipop.
The APK is signed by Google and upgrades your existing app. The cryptographic signature guarantees that the file is safe to install and was not tampered with in any way. Rather than wait for Google to push this download to your devices, which can take days, download and install it just like any other APK.
File Name: com.google.android.deskclock-4.0.1_(1906568)-40101204-minAPI19.apk
Version: 4.0.1 (1906568) (40101204)