There could be multiple reasons for this -
- Apple has done a great job of alerting users when a Wifi network is available - and you just select the network, enter the password and done. In Android, you have to manually do this - and you don't get alerted about Wifi availablity.
- Secondly, iPhone users typically use their phone more - whether on WiFi or on 3G. So chances are, they are more sensitive to usage limits, and use WiFi wherever they can.
- Thirdly, the...