Android 5.0 vs Android 4.4 - Clock & Alarms
The clock app is largely unchanged, aside from the font being a bit different and more colors being included. The on/off switches have changed to the new Android 5.0 look and feel, and colors are no longer boring and only black. That said, nothing is too different and the same simply options, repeat tabs, and days of the week are present.
It's more about being more lively and colorful, than it is changing features. At least with this app.