You may have clicked on this because you're a student in a class that's requiring you to build an app and you've zoned out and procrastinated all semester. OR maybe you want to build an app but don't quite know where to start. Either way, this list of resources below should help you create a quality app in your time-sensitive situation.
I also happen to have a lot of empathy for procrastinators, so if you are reading this at 2am the night before your assignment is due and you've run into an issue your sleep-deprived brain can't figure out, you can email me at email@example.com and I might be up late playing LoL and reply to you.
Xplatform Cloud Kit
Windows 8 App Challenge - Game Templates
Phone App Studio
Windows App Starter Kits
Windows Store Logo Resizer
Submitting to the Windows Store