Aside from sharing the S5 name and general aspect, the Galaxy S5 mini has little in common with the S5 flagship?

The Mini has a 4.5-inch Super AMOLED HD display with 720 x 1280 resolution, a quad-core 1.4GHz processor, 1.5GB of RAM, 16GB of internal storage (expandable via microSD up to 64 GB), 8MP main camera, 2.1MP webcam, 2,100mAh battery, and Android 4.4 KitKat, a heart-rate monitor and fingerprint scanner and other sensors.

The 1.4GHz processor will certainly slow it down at times, so contract price will be what drives this phone.