How to have VPN auto-reconnect?

Every VPN I've tried for iPhone will not keep its connection once you sleep and wake the phone. I see online references to an 'auto-reconnect' feature but I don't see it in any VPN settings. Was this removed? It seems like a no-brainer to have the VPN reconnect if you wake and are on the same Wifi connection. I wonder why Apple doesn't make this easier.

I saw something else about having to manually configure a VPN profile with a text editor and place it on the phone with AirDrop. Is that really the way, and does it actually work?