Can't do iOS 8.4 update

[lenjack]

Received notice of available 8.4 update. When I tapped on Software Update, there were 2 options. One is Learn more. The other is Download and Install, which is grayed out and unavailable, and does not respond. What am I missing?

 

[scifan57]

Received notice of available 8.4 update. When I tapped on Software Update, there were 2 options. One is Learn more. The other is Download and Install, which is grayed out and unavailable, and does not respond. What am I missing?

Do you have enough available storage to do the update? If your available storage is less than that required by the update, the download button will be greyed out.

 

[J. A.]

If your battery is too low, you can't update.

 

[lenjack]

fixed. had to enable wifi.

 

[scifan57]

fixed. had to enable wifi.

Good. I'm glad you got it sorted out. All iOS software updates require WiFi for downloading on account of the frequently large size of the updates.