For C4T 4, I had already made my first comment on thePEgeek.com when I received the updated C4T instructions.
The post was about the app - Motion Tennis. Motion Tennis is an app that allows the iPhone to turn into a "tennis racquet". You will need an Apple TV or AirPlay device to see the tennis game. This is a great tool to use on rainy days or to simply teach the basics of tennis. The app is $7.99 on iTunes. Some may argue that they want a free app that does this, however I think that is a reasonable price for a game this extensive. I would imagine there are many other apps you can download that are similar to this.
The other blog, iPE, is not your regular blog. This is a podcast blog! Instead of just typing out their thoughts, findings, teaching strategies, etc., Nathan Horne and Joey Feith actually blog by using a podcast. This made it much more fun for me to look over their blog. They share ideas and stories from their classrooms. There are many great websites, teacher blogs, tools, apps and general information on their blog. This was my favorite blog I've visit so far for C4T!