With the new release of Cydia it looks a bit zoomed in on iPhone 6 & 6+. But if you have Cydia installed on your iPhone 6 or 6+ this is a easy fix for you.
All you have to do is follow the steps below.

>Download the moded info.plist file witch can be found HERE.
>SSH into your device. “the same process you did to install Cydia”
>Now you need to go to the Applications folder in the file system.
>Find the folder name Cydia.app
>This is a very important part backup the info.plist file to your computer.
>Now replace the info.plist file with the one you download.
>Now you will need to reboot or respring your device.
>And now open Cydia it should now fit the screen better and not have that zoomed in look.
This tutorial was first posted by @ragemasta on his site witch can be found HERE!