as huge number of user now you can login rediffmail via mobile device. if you don't know how to login lets follow some easy steps to rediffmail login :
Download or install the application from Play store/app store
open rediffmail by tap open
after that select Allow option.
Then you can click Accept to proceed.
Now, enter your email address and click the Proceed button.
Enter your password and click Sign in. Step 7: Your personal Rediff mail will now be opened.