See GoodReader on iTunes preview
The iPad has no built-in file system, so files are stored locally within individual apps. GoodReader is my preferred app for handling files, and it provides a file storage system, complementary file handling tools (rename, zip, unzip, email, organise, and "open in other apps"), a web file download facility, connections to numerous file storage services (e.g. Dropbox, Skydrive, Windows/Apple servers, FTP), and connections to popular email/webmail services for downloading attachments.
GoodReader has an embedded web server, for directly transferring files to/from a computer over Wi-Fi, and can also transfer files to/from a computer over the iPad's USB cable, acting as an external drive.
GoodReader began life as a PDF reader, and can be used to open and annotate PDFs, documents, images and photos,.GoodReader can also play music and video clips.
Typical use cases are based on file handling, and storing files for offline access:
- Download and store files from websites (e.g. PDF documents)
- Store email attachments on the iPad (e.g. booking confirmations and boarding passes)
- Upload files from a computer to the iPad over Wi-Fi or USB cable (e.g. non-itunes music and video)