Huawei Honor 4X - Delete all contacts

Factory OS: Android 4.4 (Kit Kat)
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Delete all contacts
There are a number of ways, as below. The first two of these may be disabled on some networks/carriers or Android versions however.
1) Go to Settings – More – Application Manager. Then swipe from right to left until you are on the All screen (at the top). Then scroll down to Contacts Storage – Clear Data.
2) Go to Contacts. Then press Menu – Delete. Then press Select all (at the top) and then Delete again.
3) Go to Settings – Accounts and sync. Then untick Background data and Auto-sync. Then go to Gmail (or an account that your phone syncs with) and delete all of your Contacts from there. Then re-sync your phone.
4) Download an App called ‘Delete All Contacts’ and use that as a last resort.
The methods above will delete contacts from the phone only, not the SIM card.