Yes, you can! Are we still on for eating out? Are we still on for reading that book together? Are we still on for going out tomorrow night? Are we still on for having a night in-front of the tv?

Probably this doesn't help much, but it does normally go with a noun i.e. "are we still on for the movies?" As opposed to "Are we still on for going to the movies?". I suppose it's not wrong, as a gerund kind of works like a noun, but it does not sound natural. If you must use the gerund, it could simply be "Are we still going to the movies?"