The Wireless FAQ

FAQ Sections
01 - General
Definitions of terms and advice on getting started. If you're new to wireless technology, you should start here.

1.1 In short, what is WAP?
1.2 In short, what is WML?
1.3 How long will WAP last?
1.4 Why use WML when you can use HTML?
1.5 What is a good service for the mobile internet?
1.6 In short, what is WMLScript?
1.7 What is a WML deck of cards?
1.8 How do I start writing WAP applications?
1.9 How does a WAP device connect to the internet?
1.10 Is there a glossary of wireless technology expressions?
1.11 Can you recommend any good WAP service providers?
1.12 Is there a list of some great WAP applications?
1.13 Can you show me some simple example code?
1.14 What is the Open Usability Interface (OUI) ?
1.15 We already have a WEB site, how do we get a WAP site?
1.16 We already have a HDML site, how do we get a WAP site?

02 - Wireless development resources on the web
Links to wireless developer sites, articles and libraries.

2.1 Where can I find more info on wireless technologies?
2.2 What Open Source resources are available for the wireless environment?
2.3 Is there an updated list of Agent strings somewhere?

03 - Accessing WML contents
How to access already existing WAP sites. WAP browsers for most operating systems. WAP gateways and WAP operator environments.

3.1 How do I access WML pages?
3.2 How do I bypass my operator and connect "directly" to the internet?
3.3 Can I "surf" WAP sites without using a real WAP device?
3.4 I'd like to set up my own WAP operator service, what do I do?
3.5 Is there a list of available WAP phones and WAP devices on the market?
3.6 Where can I find publicly available WAP gateways on the internet?
3.7 Where and how do I register a WAP domain?

04 - Serving WML contents
Re-using the code and technology from the wired web in the wireless environment. PHP, ASP, Perl, Java Servlets, etc.

4.1 What do I need to serve WML contents to a WAP device?
4.2 What's with the HTTP server MIME types?
4.3 How can I use PHP to make WML contents more dynamic?
4.4 Can you show me some examples serving WAP via PHP?
4.5 How do I prevent a WML deck from being read from the cache?
4.6 How can I tell HTML browsers from WML browsers?
4.7 How do I read data from the WAP device (telephone number etc)?
4.8 Why is the HTTP User Agent string different with the Openwave.com gateway?
4.9 Is it possible to localize text in the browser?
4.10 How do I prevent variables from being stored in the cache?
4.11 How to I access a database from WML?
4.12 How can I control caching when nothing else works?
4.13 How can I use ASP to make WML contents more dynamic?
4.14 How do I pass a variable from WML to ASP?
4.15 Is there a list of other useful stuff for serving WML contents?
4.16 How do I use XSL with WML and WAP?
4.17 How can I use Perl to make WML contents more dynamic?
4.18 What is PUSHing and how does it work?

05 - WML specifics
Details on the Wireless Markup Language used in WAP device browsers. What works where.

5.1 What is the general syntax of WML?
5.2 Do all WAP devices (browsers) comply with WML specifications?
5.3 Which phone uses which UP.browser version?
5.4 Can I use HTML based developer tools to develop WAP applications?
5.5 Where can I find a WML validator?

06 - WAP development specifics
Topics surrounding the development tools used for developing WAP applications.

6.2 Where can I download the Ericsson SDK?
6.3 Why can I not access pages on the internet from my emulator?
6.4 Why doesn't Basic Authentication work with the Nokia SDK?
6.5 What is the difference between WAP 1.1 and WAP 1.2?
6.6 Where can I download the Openwave SDK?
6.7 Where can I download Microsoft's Mobile Explorer?
6.8 What's special about the Microsoft Mobile Explorer?

07 - Making it look fancy
Tips and tricks on how to stun your users by making your applications work like a race-horse and not look like a donkey.

7.1 Can WAP devices use graphical images instead of just text?
7.2 What size screens will I be developing for?
7.3 How do I use animated images?
7.4 My WBMP images look bad, what can I do?
7.5 Can I generate dynamic WBMP images on-the-fly?
7.6 How can I send e-mail from a WAP device?
7.7 Is it possible to "link" to a telephone number?
7.8 How can I prevent a form from having empty fields?
7.9 How do I use option fields when the display cannot fit all of them?
7.10 Is it possible to "preload" images in WML?
7.11 Is it possible to change the font displayed in a browser?
7.12 How do I get a WML card to refresh itself?
7.13 How do I use streaming media in WAP?
7.14 How much data can I send back to the server using GET or POST?
7.15 Can color images be used in WAP?
7.16 How does Nokia's "Use Number" function work?
7.17 What are Openwave.com WML Extensions and how do they work?
7.18 Can WML extensions be used in Europe and other GSM areas?
7.19 What is WML Extension "Mobile-Originated Prefetch" (<link> tag)?
7.20 What are WML Extension "nested contexts/activities" (<spawn> tag)?
7.21 How is the WML Extension localsrc attribute used?
7.22 How is the "accesskey" attribute used?
7.23 How can I tell which WML version a device supports?

08 - Troubleshooting
When your applications aren't working as they should, chances are that someone has already solved the problem and added the solution to this FAQ.

8.1 Why won't my WBMP images appear?
8.2 The WAP device emulator says text/html mime type is not supported, but my MIME setup is correct?
8.3 I can't get the <input/> format to work correctly. What's wrong?
8.4 I think some special characters are breaking my code or links, what can I do?
8.5 What's the size limit on each WML deck?
8.6 I can't get POST to work! What's wrong?
8.7 My ASP code works on emulators but not on real browsers. What's wrong?
8.8 Why won't my META tags work in WML?
8.9 Why aren't the server receiving the variables I send it?
8.10 Why doesn't some Mitsubishi browsers (Trium) run WMLScript?
8.11 Why is the REFERER line in the HTTP header not visible?
8.12 Why does a normal HTTP 302 redirect not work with WAP?
8.13 Why won't the Nokia 7110 POST more than 160 characters?
8.14 Why can't I pass variables with spaces and apostrophes?
8.15 I can't display a dollar sign in my WML code, what's wrong?
8.16 My WAP services only works for me, no one else! What is wrong?

09 - Security
Details on one of the most discussed Wireless Application Protocol topics. WTLS, SSL, restricting access and so on.

9.1 How can I protect certain WML pages/decks from unwanted users?
9.2 Are Sessions supported in the WAP environment?
9.3 Are Cookies supported in the WAP environment?
9.4 How secure is WAP with SSL and WTLS?

10 - WMLscript in detail
Expand your applications even further with scripts that run on WAP devices.

10.1 Where can I learn about WMLScript?
10.2 Which functions are available in the WMLscript Lang library?
10.3 Which functions are available in the WMLscript Float library?
10.4 Which functions are available in the WMLscript String library?

12 - iMode section
Start testing and developing iMode applications before the hardware hits the streets of Europe and the US.

12.1 Why is there an iMode section in this wireless FAQ?
12.2 What is I-Mode, and where can I find out more about it?
12.3 Where can I find an iMode emulator?
12.4 How is iMode different from WAP?
12.5 How does Compact HTML (CHTML) work?
12.6 How can I tell iMode browsers from other browsers?
12.7 How does iMode work?

13 - WAP Gateways and WAP Servers
How the most important part of the WAP "chain" works, which WAP gateway does what, and who makes them.

13.1 What is a WAP gateway?
13.2 What is a WAP Server?
13.3 Who is responsible for setting up the connection to the WAP gateway?
13.4 Which WAP gateways and WAP servers are available on the market?
13.5 How "compatible" are each of the WAP gateways?

14 - Short Message Service (SMS)
Probably one of the most under rated, but still well used extras of GSM.

14.1 What is SMS?
14.2 What can SMS be used for?
14.3 What is EMS?
14.4 What is MMS?

A - About this FAQ
Information on who maintains the FAQ, how content is added, and a big list of thanks to those who have helped the FAQ become what it is.

A.3 Where can I test the examples applications in the FAQ?