Drum Pad Free is one of those apps that gives you exactly what it promises without frills or gimmicks. No hidden menus. Just a simple drum pad app that works as advertised with no unwanted upgrade banners flashing across the screen. Of course because it is free and admittedly very limited in what it allows you to do, Drum Pad (Free) isn't right for everyone.
The app is very easy to use. Open it and you are presented with nine drum pads. Tap each of them to make a noise. They are each labeled with the associated sound they make--crash, tom, ride, hi-hat, snare, etc.--so it is easy to see what you can do with them, and they are color coded if you ever get quick enough to play by touch. That said, the app doesn't do anything else. There are no recording or sharing buttons, no menus, and no upgrades for additional features, so the actual functionality of this app is fairly limited. There is a single ad bar that is mostly out of the way, and there is no way to remove it.
That said, if all you are looking for is a drum pad app on your phone that is accurate and easy to use, this is as good as any. It's not a full-blown instrument and you won't be using it to compose songs any time soon, but it's a fun toy that allows you to practice beats on the go.