Last week Twitter had rolled out a new change to Twitter web and its apps in iOS and Android, the header photo or cover photo. The header photo is similar to that found in Facebook and Google+ and allows users to add their own photo. You can upload your header photo, which appears above your Tweets, to express yourself instantly, anywhere.
Twitter Header or Cover Photo Size:
To upload a header photo to your Twitter page, click on the gear icon in the top-right of your Twitter.com page and select “Edit profile.” Click “Design” from the menu and scroll to the bottom. Under “Customize your own,” you’ll see the option for header image. Here, you can upload your own image, but be sure that the minimum dimensions are 1252×626 and that it has a file size smaller than 5MB.
Your changes will appear instantly, but they’re not saved until you click “Save changes.”
Now you can see the new header or cover photo available across web, iPad, iPhone and Android.