This guide explains how to combine the wonderful new techonologies Mozilla Prism and Google Gears with Gmail to create a fully fledged desktop application that works also in offline mode. It is tested on Mac OS X Leopard, but it should be done the same way under Windows and Linux. In the same way you can also build a stand-alone rss reader using Google Reader. It should basically work with any Gears enabled website, including Google Docs, Google Calendar, Worpress, etc. (not tested yet).
UPDATE: successfully tested also with Google Reader, Google Docs and Google Calendar. Works like charm, just the Calendar does not allow you to add events in offline mode – disabled by Google, not sure why.
Here is the screenshot of the result as a proof I am not kidding and it works 
So here we go:
- Start Firefox and install Prism add-on, if you didn’t before (http://prism.mozilla.com/).
- Grab a nice big Gmail icon over at Iconspedia.com
- Go to http://mail.google.com
- In Firefox, select Tools-Convert Website to Application. You may want to change the URL to http://mail.google.com. Change other settings as you wish and use that nice Gmail icon we downloaded before.
- If you are lazy as me, download the amended gears.xpi directly and proceed to step 12.
- Grab Gears XPI file (Mac/Lin/Win) over here: http://65.30.72.135/prism/addons/ (thanks Matthew!)
Open Opera or Safari and go to http://gears.google.com. Click the tiny “Firefox” link on the right. We are doing this in Opera, because we need to download the XPI file, instead of automatically install it in Firefox. So press “Install” and then “Agree” and you should download a gears-osx-opt.xpi file (On windows you need to find the XPI file somewhere via google, instead of the EXE installer – that should be the only difference – let me know if not, please) - Open the XPI file with Stuffit Expander (It’s a ZIP file, just with XPI extension) or your favourite ZIP application
- Browse to the unpacked folder and open the file install.rdf in TextMate or your favorite text editor
- Find the section
- Replace the whole section with this:
prism@developer.mozilla.org 0.8 1.1.* Save and close
- Now compress again the previously uncompressed folder. Make sure you are archiving the folder contents, not the folder itself! Change the zipped file extension to XPI again. We have the Gears plugin ready now
![:-)]()
- Run the Gmail.app previously created by Prism
- Click that gear icon in the bottom right corner and select Tools-Addons
- Drag and drop the XPI file into this new window, it should start the plugin insallation. So continue with the installation and then restart the Gmail.app
- Now log in to gmail with your login info
- Go to Settings (link on top right) and select Labs tab
- Select Offline (should be the first item) – Enable and Save the change
- Return to mailbox. Now you should see a link “Offline” on the top right. Click it and follow the instructions
- It should then start Syncing. This takes some time first time
- If everything went ok, you should now have fully functional stand-alone Gmail client application. Enjoy!
Please leave a comment if this guide works for you. Also please share it, if you find it useful.
