MCPatcher HD Fix is the latest version of MCPatcher for Minecraft which allows you to easily switch between texture packs in Minecraft. To install MCPatcher HD Fix, simply double click on the Patch file. Then open Minecraft, click Mods and Textures Packs and select the pack you want. Of course, you need Minecraft texture packs already installed or downloaded to switch between them. If you still can't see them, make sure you go to the Minecraft root folder and copy and paste some texture packs into the "texturepacks" folder. Note that on Macs, MCPatcher HD Fix is a Java application.
If you want to switch between texture packs more easily in Minecraft, MCPatcher HD Fix is an effective solution.