In the “Contacts” interface, you can modify or delete the existing contacts in your phone. You can also add and group contacts according to your requirement here. Of course, all operations are conducted in local computer. After completing the modification, you can synchronize the modifications to your phone through the “Sync to Phone” on the lower right corner. There will be a success info when the synchronization completes.

By clicking the letter list on the right panel, you can sort the contacts according to the initial of the first character of their names.