Re: how can i downdlao you tube videos on my iphone 4
The exact steps required to download the video will depend on what tool you're using. Different tools have different settings and steps. Follow the steps for that tool. When you're saving a video, save it in MP4 format (some tools won't give you this choice, but instead just offer the option create a video for iPhone/iPod; that works, too).
When the video is done downloading, it will either be saved to your computer or in the app you used to create it on your iPhone. If you downloaded the video on an iPhone, skip to step 6. If you saved the video on a computer, drag the video into iTunes to add it to your iTunes library.
With the video now saved in iTunes, sync your iPhone with your computer. In the Movies tab of the iTunes syncing screen, check the box next to the video you just downloaded from YouTube. Click the Sync button in the bottom right corner of the screen.
If you saved the video using an app, the video could be in more than one place. It may be saved directly in the app you used to download it. If so, you should be able to watch it there.
If it's not saved in the app, check the Videos app. In it, you'll see all the videos on your device, including the one you just added. Tap it to watch the video.