How to erase all contacts from an Android phone?
There are about 3200 contacts.
The full story
I don't manage my contacts with Google Contacts, but with another tool that can export to the VCF format.
The first time I imported my VCF file into Google Contacts, my Android phone synced and got all contacts, perfect.
After a while, having new contacts, I exported to VCF again, and imported again to Google Calendar. All contacts got duplicated on the phone.
I removed all contacts using Google Contacts web interface in Gmail, and re-imported, but contacts get duplicated every time.
I just want to start from scratch, remove all contacts, and import from my new VCF file.