Question always arise who is best?

Comparison FlagshipWhenever it comes to flagship smartphone always first question comes which is best and why?. Here is hardware comparison of Samsung Galaxy S6, HTC One M9, LG G4, Sony Xperia Z4 and Asus Zenfone 2.

Smartphones SAMSUNG GALAXY S6 HTC ONE M9 LG  G4 SONY XPERIA Z4 ASUS ZENFONE 2
Processor Quad-core 1.5GHz Cortex-A53 & Quad-core 2.1 GHz Cortex-A57

With Exynos 7420

Quad-core 1.5GHz Cortex-A53 & Quad-core 2GHz Cortex-A57

With Qualcomm MSM8994 Snapdragon 810

Dual-core 1.8GHz Cortex-A57 & quad-core 1.44 GHz Cortex-A53 with Qualcomm MSM8992 Snapdragon 808 Quad-core Cortex-A53 & Quad-core Cortex-A57 with Qualcomm MSM8994 Snapdragon 810 Quad-core 2.3GHz (4 GB RAM model)

Quad-core 1.8 GHz (2 GB RAM model) with intel Atom

Display Super AMOLED capacitive touchscreen, 16M colors

5.1-inch

Super LCD3 capacitive touchscreen, 16M colors

5.0-inch

IPS LCD capacitive touchscreen, 16M colors

5.5-inch

IPS LCD capacitive touchscreen, 16M colors

5.2-inches

IPS capacitive touchscreen, 16M colors

5.5-inch

RAM 3GB RAM 3GB RAM 3GB RAM 3GB RAM 2GB/4GB RAM
Memory Internal 32/64/128 GB

No card slot

Internal: 32GB

microSD, up to 128GB

Internal : 32GB

microSD, up to 128GB

Internal : 32/64 GB,

microSD, up to 128GB

Internal :16/32/64 GB

microSD, up to 64GB

Camera Rear 16 MP, Front 5MP Rear 20.7MP, Front 4MP Rear 16MP,

Front 8MP

Rear 20.7MP, Front 5.1MP Rear 13MP, Front 5MP
OS Android OS, v5.0.2 (Lollipop) Android OS, v5.0 (Lollipop) Android OS, v5.1 (Lollipop) Android OS, v5.0 (Lollipop) Android OS, v5.0 (Lollipop)
SIM Nano-SIM Nano-SIM Nano-SIM Nano-SIM Dual SIM (Micro-SIM, dual stand-by, dual call)
Battery Non-removable Li-Ion 2550mAh Non-removable Li-Po 2840mAh Li-Ion 3000mAh Non-removable Li-Ion 2930mAh Non-removable Li-Po 3000mAh
Connectivity WLAN/ Bluetooth/ GPS/ NFC/ WLAN/ Bluetooth/ GPS/ NFC/ Radio WLAN/ Bluetooth/ GPS/ NFC/ Radio WLAN/ Bluetooth/ GPS/ NFC/ Radio WLAN/ Bluetooth/ GPS/ NFC/ Radio
Network GSM/HSPA/LTE GSM/HSPA/LTE GSM/HSPA/LTE GSM/HSPA/LTE GSM/HSPA/LTE