Teachers have to start with the objective when deciding how to educate kids. We can't just think of something "fun", do it, and think we have contributed to their education. It's not any different when we use technology. I have to start with the objective. What do I want the kids to know, then decide what technology can be used to meet that objective.
Students must always be held accountable in some manner for what we ask them to do. I want to know what they got out of an activity - what they learned. This can be done in many ways, but it's not any different just because they are doing stations with technology.
I found a couple of neat interactive websites to use in the classroom. I like the Make Your Own Mission on the Thinkfinity website. I could use this during our solar system unit. As a part of this activity I could have kids write a blog about the problems they encountered while making the mission, why they chose the things they did, etc. I also like the Save Our Dumb Planet on the Mangahigh website. It's a great way for kids to practice writing equations of lines while playing a game. I could have the students write down their score when the finish.
I found a NASA app for the iPad that is great. NASA always has such good resources for teachers. This app has launch and mission information. Students could follow the progress of a mission (from launch through data collection). They could write reflections on their blog. I also found a Build.A.Body app. The students drag the organs to the correct locations on the body. A way to hold students accountable is to have them write down their time (time it took them to complete the system) to encourage improvement. This could easily be done as a station - either during the initial learning of the material or as a review.
I would love to let students find apps that they enjoy and reflect on their learning. Students know when they like something and they know when they are learning (or not). If I can give them some responsibility for their learning and hold them accountable for that learning, then their motivation is more likely to be high.