What technology is allowed is decided on an order by order basis. Around here electric in the house is always forbidden for Amish as far as I know. For battery tools and other electronics there is usually a designated shed or barn that has electric, possibly shared by multiple homes. Any devices live in that building when not in use. There is a set time window during the day that they are allowed to be used and they must be back there by the devices curfew. Orders might limit the hours power is on in that building also. There will also be rules for how they can be used when they are in use as well.