Mobile devices, mainly Google's Android and Apple's iOS, are rapidly spreading throughout education. The security of these devices and their operating systems are very important to schools. Every system has weaknesses and no system is totally secure or safe from attack. In addition to security, schools should look at cost and functionality of the devices.
While I've used Apple devices before (friends' and coworkers'), I own Android and webOS devices.
Here are some great resources about Android Apps and devices:
Android 4 Schools
Android Smartphone and Apps I use as an Educator
Android Resources, News and more
Great Resource for iOS - tips, app reviews, hardware reviews, news and more
Here is a great infographic from VeraCode that examines the security features of Android and iOS, and also takes a look at their strengths and weaknesses.
Infographic by Veracode Application Security