Installing Java applications on Nextel phones
Unlike most other wireless carriers, Nextel does not allow you to directly download Java applications from third party web sites to your phone.  Nevertheless, it is still possible for you to install Fone Folio.  To use any of these methods, you'll first need to download the Fone Folio .jad and .jar files from the download page of this site to your computer.
BlackBerry® Application Loader
If you have a RIM BlackBerry® and you're using BES, you should be able to download Fone Folio over-the-air.  Otherwise you can download a zip file containing the ALX & COD files and use the Application Loader to install Fone Folio on your device.
Nextel Mobile Applications Manager
One of the tools Nextel provides for account management is their Mobile Applications Manager.  This tool allows you to upload Java applications to your account and then have them available for download from your phone.  It's currently included with all Data Access plans (except Pay As You Go).To use Mobile Applications Manager, you first have to be registered to manage your account under 'MyNextel'.  Once you're logged into MyNextel, go to My Online Tools > Mobile Application Manager and follow the directions.