Does Netflix on the iPhone Require Wi-Fi?by John Lister
One of the benefits of having an iPhone is the ability to stream Netflix video anywhere over the Internet, which is possible on all iOS devices through a dedicated app. The required Internet connection can be either Wi-Fi or a cellular connection such as 3G. However, streaming Netflix over 3G can cause problems with data plan caps, so the Netflix app enables you to set it to work only over Wi-Fi.
Although Netflix is an online service with a Web interface, you won't be able to watch videos on the website using your iPhone because the phone doesn't support Flash content. Instead you must use a dedicated iPhone app available from the App Store. There's no charge to download or install the app, but you'll need a valid Netflix subscription to use it.
Netflix is a streaming video service, meaning you don't download video files but rather watch them as if they were a live broadcast -- though you can rewind, fast forward and pause playback. This means that watching videos from Netflix on the iPhone is possible only if you have an active Internet data connection. The app doesn't care whether it's a Wi-Fi network or a 3G or 4G data connection. Wi-Fi could provide a smoother playback experience with fewer dropped connections, but cellular networks range farther and enable you to keep streaming while you're moving.
Many cellphone networks have fixed monthly usage limits on some or all of their cellular data packages. Since you usually don't download large files as you might on a desktop or laptop, streaming video will often be the smartphone use that consumes the most data. Clicker, an Internet TV guide, found that Netflix streaming uses an average of 2.5MB for every minute of video on an iPad. This would mean a 2GB data plan would enable a maximum of just under 14 hours of streaming video over 3G or 4G each month, assuming you didn't use your data connection for any other purpose. Data consumption may be slightly less on the iPhone as it has a lower screen size and resolution, but there's still a significant risk that Netflix streaming could contribute to hitting your monthly limit. Depending on your service agreement, the consequences of this could include paying overage fees for the excess data use, having your data connection slowed for the rest of the month, or having your data connection blocked for the rest of the month.
IPhone App Settings
Until May 2012, the Netflix iPhone app would automatically try to connect via whatever method was available to get online, whether it was Wi-Fi or 3G/4G. This could cause problems with excessive data use over 3G/4G, particularly if the phone and app connected this way without you realizing it. For example, you might be in range of a Wi-Fi network but not realize you hadn't connected to it and instead unintentionally connect through 3G/4G when you start the app. With the May 2012 update, if you open the "Settings" menu, you can set your iPhone to connect only via Wi-Fi. This isn't a default setting, so you must have the latest edition of the app installed and updated, and then manually change the setting.