I know that on Facebook and Twitter you can schedule ads and posts so that question should be answered.

I know in Facebook you can target users by whether they're using a mobile or desktop device and also by which operating system they're using i.g. iOS or Android

You can also target by interests like 'Running' or 'marathons' based on their profile and activity or you can use partner categories to target people who spent money on fitness/running equipment or possibly even registered for a marathon.