Imagine yourself how annoying it would be when you start surfing the web at home and the Wi-Fi network to which you are connected either slows down or stops transmitting data altogether. You want to check your mail but the messages are not loading, it's just spinning but with no results. Agony is more when it comes to fixing this issue. You have to either turn the Wi-Fi off on your iPhone manually in order to totally disconnect from the close-enough router and then switch over to your cellular data or reset the router settings.
As a solution to all the Wi-Fi connectivity miseries faced by the iPhone users, the iOS 9 update has come up with the Wi-Fi Assist. This software update intelligently switches on your mobile Data during sessions of poor Wi-Fi connectivity. With this feature your iPhone is allowed to access cellular data when Wi-Fi is poor. It seems like a simple toggle which you can enable just once and thereafter it will automatically do the swap for you.
Even though the feature is dubbed as 'Wi-Fi Assist' the option can be spotted under the 'Cellular' menu in the iOS settings app. When you turn this on the device will be forced to get itself connected to a 3G or 4G network connection if the Wi-Fi data transmission falls short of an unspecified signal strength.
The date of the release of this update with this amazing feature has not yet been announced by speculations suggests that we can expect this new version of the OS by September.