Compose Email Shortcut

It is not possible. The only shortcuts that can be added to the home page are web links.

Well it is possible, though I am not good at making a data url. Many sites such as http://springlets.com and http://iwebsaver.com offer ways of saving things to your home screen via data url's. These urls can hold entire pages in the url itself. So, a url can be made as a data url and the data in the url can be simple javascript for a mailto tag, thus allowing the mail app to start. Though the process will make Safari open for a moment, it will run the javascript thus start the mail app. Sort of round-a-bout, but possible.

I use http://springlets.com for the quick phone dialing. I know I don't really need it, but nice having a button on home screen for very quick dialing at times. And gives a reason for another icon 😉

I have then used http://iwebsaver.com to convert some web apps (mainly some games) into data urls so I can actually play the webapps (games) even in airplane mode since all the data of the page is in the URL (note, depends on how game/webapp is designed if it will work for the ones you may have).

iWebSaver now lets you achieve this more easily. You can save links on your homescreen to email certain addresses, or just create a link on your homescreen to compose an email to no one in paricular. To add a simple "Write Mail" link to your homescreen, just go to this URL and follow the instructions:

http://iWebSaver.com/?u=mailto:

If you want to create a shortcut to send mail to a particular address, just add the email address to the end of that URL.