Accessing your Email
You can access your email through your mobile phonesomething that just makes sense with iPhones and Droids. The most direct way to access Apps Mail is through a mobile browser. You'll just enter the URL for your school's domain (which is http://mail.google.com/a/myschool.org, replacing myschool.org with your actual domain name) and log in into your account.
There is a mobile application, "GMail for Mobile" that you can download to some supported phones. This application does sync your email between the Apps Mail software and your phone. You'll need to know how to configure the phone for accessing the Google Apps for Schools and not just the regular old GMail account.