Wi-Fi Assist only works on iPad models running iOS 9 or later and may not be supported on older models. It also only works on Wi-Fi + Cellular models since you need cellular radios to connect to 3G and 4G LTE networks. To enable Wi-Fi Assist navigate to Settings > Cellular and scroll down until you see the Wi-Fi Assist slider. Tap the slider so it is GREEN / ON.
Why won't Wi-Fi Assist work on my iPad?
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