We just added SSL to the site. Logging in and adding data to the site will be more secure now.
All of the data you post at Fuelly might be public, but your password and email address should always remain a secret between you and Fuelly. We just made some pages at Fuelly more secure with an SSL connection to improve security.
Different browsers show that you have a secure connection in different ways. Most show a green bar next to the URL in the address bar that includes the name of the company. (Our parent company name is MetaFilter Network, Inc.)
You shouldn't notice a big change, just know that if you happen to see secure pages as you're using Fuelly—we meant to do that. If you have any problems, please contact us (securely) or post them here (securely).
No, my guess is that you have cookies disabled on your iPhone. Seems to be a common problem for some reason. You can check by going into your iPhone Settings, Safari, and make sure "Accept Cookies" is set to "From visited" or "Always".