What is the worst smartphone you have ever owned?

I made a terrible decision when I bought the Lenovo Phab 2 Pro. Have you also experienced the same? Which phone did you have the worst experience with?

Levo PHAB is now available for sale at Flipkart

The Lenovo Phab First Sale is on 21st April exclusively on Flipkart. Registrations are required to buy the Lenovo Phab (Phone + Tablet)

The Lenovo Phab a quad-core 4G enabled phablet (Phone + Tablet = Phab). Registrations for the same has already begun. The Phab from Lenovo is a quad-core powered that sports a 6.98-inch touchscreen.

Specs
Android v5.1 (Lollipop) OS
13 MP Primary Camera
5 MP Secondary Camera
6.98 inch Touchscreen
1.2 GHz Qualcomm MSM8916 Quad Core 64-bit Processor
Wi-Fi Enabled
Expandable Storage Capacity of 64 GB