The new Twitter profile is here. We dissected it a few days ago, but at the time, only a few celebrities and new users had the option. Now it’s available to everyone.
You’ll only see the option to change your profile from the desktop version of the app. If for some reason, Twitter doesn’t prompt you to change your profile, go to Settings > Profile and you can upload your cover photo, etc, from there. Once you upload the cover photo, it prompts the change to the new look and feel.
In other words, for those of you who tweet from Hootsuite, Tweetdeck, and your mobile devices, just take a moment and log into twitter.com. Once you update your cover photo, etc, several of the changes will be reflected in your profile page on the mobile app. Things like popular tweets and pinned tweets are not mobile (yet).
The perfect size for your new Twitter cover image is 1500×500. Yeah, it’s big. Twitter will resize for you and, like Facebook’s cover image, you can reposition. The cover image will then be reflected on your feed/tweet stream page as well, but tiny and behind your profile photo.
The maximum file size, by the way, is 5MB. If you upload something bigger, it will show up for a moment but it won’t stick, so be cognizant of your MBs.