Carrier Bundles provide a way to organize all customizations related to carriers in one place. These include voice mail numbers, MMS and APN settings etc. For users on carriers other than the Apple's official partners, carrier bundles allow to configure important settings such as APN and enable features like MMS and tethering.
How to install IPCC?
1. Download the latest 3uTools on a PC/laptop, connect an iDevice to the PC/laptop with a USB cable.
2. After connecting the iDevice, go to "Toolbox → Install IPCC".
3. Before the installation, you will need to get the IPCC file from a firmware you have downloaded. (Click here for how to get an IPCC file.)
4. Now you get a .ipcc file. Select the .ipcc file in "Select File", and then click "Install".
5. Click "Yes" on the pop-up windows to proceed the installation, or click "No" to cancel the installation.
6. You will wait for 2 seconds after clicking "Yes" for the installation of the IPCC file.
7. You may check the version of IPCC by going to "Settings → General → About → Carrier" on your iDevice.