Getting Started With Palm Query Application Development

Introduction

A Palm Query Application, or PQA as they are commonly called, is a special type of application for Palm VII devices that allows a user to interact wirelessly with Web content. A PQA takes the concept of interactive Web browsing a step farther by consolidating related, static content into an application that can be installed on a Palm VII device. Links within a PQA document can either refer to other pages within the application or they can refer to documents or scripts residing on a publicly available Web server. The pages retrieved from within that application result in no wireless data transmission. Pages not in the PQA, naturally, result in a wireless HTTP request. Before diving into the specifics of Palm Query Application development (it's painless...honest!), let's first spend a moment explaining what the Palm VII is and what its capabilities are.

The Palm VII Organizer

The Palm VII Connected Organizer is the first mass-marketed and mass-produced electronic organizer with wireless capabilities. The engineering design behind the product is worthy of a separate article in itself, but we won't bore you with the details here. Suffice it to say that Palm was able to design a handheld device that is nearly the same size and weight of a Palm III with the same memory, display, and operating system plus a wireless modem and antenna...all with no noticeable performance or power degradation! Just as impressive is the way that the device operates using the Palm.net service (based on the BellSouth Wireless Data network). The process to setup an account on the network and begin retrieving PQA data (known as Web Clippings) is very streamlined. Simply lift the antenna for the first time, enter in user information and a credit card, select the service you want (designed to accomodate light users all the way up to "power" users), and you're ready to roll! The Palm VII comes pre-installed with a number of useful PQA's including those from Amazon.com, Yahoo!, MapQuest, and The Weather Channel. All are impressive in their own right and provide real-world examples of the power of wireless information access. For instance, the Amazon.com PQA ties your wireless access to your "One-Click" account information set up on their standard Web site. Doing this eliminates the need to reenter address and credit card information and allows the user to simply click and buy wirelessly. Very cool (and dangerous for the impulse buyer!).

What is WLAN?

What is WLAN?

WLAN - stands for Wireless Local Area Network. WLAN is a flexible data communication system implemented as an extension to, or as an alternative for, a wired LAN within a building. WLAN technology is being widely used to provide wireless internet access in public places like airports, hotels, and shopping centres but it is also increasingly being used in the home and office to allow computers to access the internet and network with each other without the need for special cables.

WLANs use radio waves in the 2.4 and 5 GHz range to transmit and receive data over the air.

What research has been undertaken?

The use of radio waves has been the subject of scientific research spanning more than 50 years. In that time, a wide variety of frequencies as well as modulations have been studied to determine whether there is any impact on our health. This large and growing body of research has been constantly reviewed by numerous independent scientific expert panels, government agencies, standard-setting organizations and health authorities from around the world. All have reached the same general scientific conclusion: that there is no established evidence of any adverse health effects from exposure to radio waves within the limits applied to mobile communications systems.

Are there safety limits for exposure to radio waves?

Yes there are. It is worth remembering that the use of radio waves is a common part of our everyday lives and bring us the benefits and enjoyment of television, radio and mobile phones. From the research that has been undertaken, safety limits have been established to provide protection for all members of our society - from the young to the very old.

These standards, endorsed by the World Health Organization (WHO) and other authorities around the world, establish exposure limits based on extensive reviews of all available scientific evidence and include substantial margins of safety to protect both users and the public. Member companies of the Mobile Manufacturers Forum test their products to assure their adherence to these rigorous safety standards.