Searching for any type of classified ad is easy, and so is publishing your own. All you have to do is create an account, a process that takes just two minutes. That done, you can start posting classified ads on Gumtree.
Gumtree ads allow you to view and add a lot of information. If, for example, you're trying to buy (or sell) a car, you can filter by the type of fuel used, make and model, mileage, year of production, etc. With real estate, you can do the same: filter by year of construction, number of rooms, and so on.
Gumtree is an excellent app for classified ads, though it's really only useful if you live in or plan to visit the UK.
Requires Android 4.0 or higher