From All Contacts, tap the appropriate contact then tap the Edit icon (located in the upper-right).
Enter any of following information then tap the Done icon (located in the upper-left).
To change the account type, tap and scroll down then tap the desired account (e.g., Blackberry Hub, Cloud, Google).
Depending upon the account type, the options presented may vary.
Add another field (Phonetic name, Organization, IM, Address, etc.)