Unlike most computers, the iPad isn’t designed to be a multi-user device. iOS doesn’t support multiple user accounts or profiles – that essentially means one set of device and application settings along with a personal collection of information like notes, email, browser bookmarks, and stored passwords for different online services. Sharing a device with that much personal data makes it easy for someone to snoop while using another person’s iPhone or iPad or on an iPad that is commonly shared between multiple users.
Passtouch is a web browser for the iPad that’s designed to offer at least some multi-user capabilities as well as to secure web-based information like bookmarks, cookies, and stored passwords. It doesn’t offer whole-device accounts or profiles but it does offer some extra security for devices that are regularly shared.