Can I use quick detailer over a ceramic coating?
Quick answer: Yes -- you can use a quick detailer on a ceramic-coated car. Choose a coating-safe product (often SiO2-based) and avoid wax-heavy sprays. Use it after washes as a drying aid, but not in the first week while the coating cures.
Yes, you can. They might not be your best option though, and it depends on what you want out of them.
A car wax contains waxes and oils -- waxes for protection and longevity, oils for shine. A quick detailer or show shine product is essentially heavy on oils and light on waxes. They are easy to use and put on a nice shine, but do not last long, often only days. Depending on the product, some have a mild cleaning ability too, which is the case with dry-wash type products.
The bottom line: they should not do your ceramic coating any harm. They might leave a residue build-up over time, but it usually washes off. We would not recommend them for trying to boost the shine of a coated car -- the coating already does that job -- but for quick detailing to lift contamination between washes, they are a decent idea.
If you use one, apply it only to clean paint with a clean microfibre towel, use less product than you think you need, and skip it during the initial cure time after a fresh coating. If your goal is refreshing water behaviour rather than just gloss, a ceramic-compatible topper is designed for that job and will do it better.
Tom, our operations manager, made a related observation: after a year or so, most coatings still bead, but the response is rarely as sharp as when they were first applied. Every car that has come back to us has had some level of contamination on it -- and that's usually what's dulling the water behaviour, not the coating itself. A quick detailer lifts surface dust and adds gloss, but a proper clean followed by a ceramic-compatible topper is what actually restores it.
For the broader "how to wash and look after a coated car" answer, see how to wash a car with a ceramic coating.