The method for erasing contacts from a smartphone varies depending on the brand. Both iPhone and Android devices require you to open the Contacts app, select the Edit button on the contact and choose the Delete option. On a Windows phone, open the contact, then choose More and Delete.
All smartphones have a special app that manages your contacts and the accompanying information. The iPhone's Contacts app saves contacts directly to the phone's hard drive, but also has the ability to import contacts from the phone's SIM card. To delete a contact from an iPhone, launch the app and open the contact. Click on the Edit button at the top of the page, then scroll down to Delete button at the bottom and tap it. It is also possible to download third-party apps to manage and delete your contacts, though Apple does not endorse such products, as of 2015.
The method for deleting contacts from an Android smartphone is the same as with the iPhone. However, Android devices also import contacts from a Gmail account. To delete these contacts, you must sign into the account from a computer. To delete contacts from a Windows phone, open the People app and choose the specific contact you want to delete. Tap on the More button, which contains three horizontal dots, and choose Delete from the available options.