I think there's too much color contrast - but that's just me. Plus, and sorry if this is your app, but there are other nicely done calendar apps that do not cost $2.50. I realize developers deserve compensation for great work, but with the lacking amount of official apps and with third party companies needing to pick up the slack - and charging money for them whereas official apps are normally free - one must be selective in which apps to pay for. For example, on any other platform, Feedly (an RSS reader) is free. However, because the official Feedly company refuses to support WP8 at this time, we are forced to look for third party apps like NextGen - which is $2. Don't get me wrong, NextGen is a fabulous app. However, by the time you find all of the other apps you want, you can rack up some serious cash. So that when you decide to find a decent calendar app - a lot of people are going to seriously consider a $2.50 price tag.
Just my two cents.