wifi assist not working

The strength of the Wi-Fi connection between the router and your device is what primarily determines if Wi-Fi Assist kicks in or not. So if you have a router with no outside internet connection, but works just fine for other uses internally, then Wi-Fi assist will not override a good Wi-Fi connection to connect your iPhone to the internet. Is that your situation?

Surely the clue is in the question?

BronM4 wrote:

My iPhone 5s won't use cellular data when connected to wifi even though wifi assist is on. When connected to a wifi network that doesn't have internet access it is unable to connect to the internet. Safari, Whatsapp and BBM become useless. Can anyone help???

If you want access to the Internet you must connect to a network that has access. You might have a strong Wi-Fi signal which could preclude Wi-Fi Assist from kicking in.

These exclusions from About Wi-Fi Assist may be relevant:

• Wi-Fi Assist will not automatically switch to cellular if you're data roaming.
• Wi-Fi Assist only works when you have apps running in the foreground and doesn't activate with background downloading of content.
• Wi-Fi Assist doesn’t activate with some third-party apps that stream audio or video, or download attachments, like an email app, as they might use large amounts of data.

tt2