DampApp Pro records why a Singapore ceiling, wall or wardrobe has gone mouldy: air temperature and humidity, surface temperatures, dew point calculated on the device, and the photographs and locations that tie them together.
Air-conditioning is often part of the story. A chilled duct, diffuser or pipe that sits below the dew point of the surrounding air will collect water, and a blocked condensate drain can leak. Record what was running, what could be accessed and which surfaces were below dew point, so the recommendation targets the cause rather than the stain.
Ceiling leaks are the other everyday case. HDB explains that water from the flat above can leak through the concrete floor slab, usually because the waterproof membrane and screed have worn, that this is common in older buildings in toilets and bathrooms, and that untreated leaks can cause mould. Leaks within flats are a shared matter between neighbours, while leaks from common property go to the Town Council. Dated photographs and readings from both flats make that conversation easier.