Dunlop and many other guitar or guitar-accessory companies offer two different types of cleaners, one for fretboards, the other for the finished part of the guitar. Fretboard cleaners usually contain oils (lemon is popular for its cleaning ability) to replenish those lost from the unfinished wood. You can use these materials on bridges and other unfinished surfaces. Most urethane finishes tolerate lemon oil, but some other finishes may dull over time. Urethane doesn't absorb the oil, so it sits on the surface and is a chore to fully remove - it will get sticky and attract dust as it dries.
Cleaners usually don't have oil, and are usually water-based. Don't use them on unfinished wood or surfaces with cracks or damage. The wood will absorb the water. Some cleaners are called "polishes" but have no polishing components (such as abrasives), merely cleaning components. Read the label - many are safe on matte finishes. If I recall correctly, the Martin "polish" is really just a cleaner.
Other wood or furniture oils like teak oil are generally safe, but again have to be fully wiped off the surface to avoid getting messy later. I like to use a wood oil on older ukes and guitars because it will soak into any breaks or cracks in the finish and get into the wood below, to help protect it. Newer ukes are unlikely to have that sort of surface damage.
Best to use cleaners made for guitar bodies, since they are generally safe. Windex and other commercial or household cleaners contain ammonia or alcohol, so they will also dull the surface (as well as damage the unfinished wood).