FlexHeal

FlexHeal maximises effective healing for priests by eliminating overhealing. It does this by selecting and casting the minimum healing spell and rank necessary to heal your target, taking into account all your bonuses to healing. It monitors what the healers around you are doing and changes or aborts your cast if one of them is about to heal your target.

FlexHeal also casts your healing trinkets and Inner Focus automatically. If you have CTRA it supports single-click healing; right click someone in CTRA's raid view to heal them.

To install FlexHeal, expand the zipped files into your Interface Addons folder. When you next run WoW, drag the FlexHeal macro it has created onto your actionbar. Ensure you have the 'Load out of date add-ons' option checked on your add-on screen; although this is version 12 it works perfectly well with WoW 12.1.