Here I would like to share my personal experience with people who would like to playback YouTube videos on iPhone.
Firstly, I would like to recommend you a useful program to convert YouTube video on iPhone, iPad or iPod – XFreesoft Video Converter for Mac.
1. Download, install and run XFreesoft Video Converter for Mac
There are many video converters available for you. And most of them offer free download, such as iTake Video Converter, Acrowsoft Video Converter, MacVideo Video Converter, and so on.
2. Load YouTube video
Click “Add” to import your YouTube video to this video converter. There are four buttons including Remove, Clear, Move Up, and Move Down for you to manage your source files. And the following is its main interface.
3. Edit the YouTube video (Optional)
If you want to edit your YouTube video, just click “Edit” button on the tool bar.
You can crop the frame size; add special effects like Old Film, Gray, and Negative to YouTube video; trim the video length, embed watermark.
4. Set the output options
Select the proper output format and destination folder for your YouTube video.
It even allows you to configure the resolution, frame rate, bit rate to maintain the high quality of YouTube video.
Click “Start” button to convert YouTube to MP4.