TT-SH08 This model is perfect for a great Smartphone (Note 4)

The suction cup is rather big (O78 mm)
The membrane of this sucker is sticky to adhere better to the plastic dashboard (not tried as used on windshields). The manual says that one must clean after use with a cloth soaked in soapy water.
The joints allow a multitude of positions, so we get visually conceal the cup behind the phone.

The 2 legs clutching the phone are rubber coated and are effective through a system maintained by notches. Pressing a button loosening. The small folding flap (for portrait mode) is not really necessary.

The guarantee states 12 months extendable to 18 (registration)
Only the visual quality of the plastic can be criticized, but for the price it is negligible.