NEW YORK ( TheStreet) -- Ever tried downloading a mobile app and find that it just doesn't work? The problem may be more common than you think -- over 75% of apps go live without being tested, leading to bugs, poor design and security flaws. A new group of start-ups is hoping to address this problem by developing testing solutions for companies and brands looking to try out their mobile apps in real-world conditions prior to launch. uTest, based in Southborough, Mass., provides so-called crowd-sourced mobile app testing. Companies ranging from Google ( GOOG) and Groupon ( GRPN) to small start-ups submit their apps to uTest which are then tested for kinks by its community of over 50,000 professional testers. uTest offers several types of testing, including functional (ensuring features such as log-in and installation work properly), load and performance testing (making sure the app is prepared for peak usage times) and security testing (keeping the app safe from hackers). Apps are also tested across a variety of platforms, including iPhone, Android, BlackBerry and Symbian, as well as a handful of carriers and geographies to ensure they can perform under different conditions. "Especially in the Android environment there's no such thing as a single platform," said Carlos Montero-Luque, SVP of Engineering at Boston-based Apperian, which helps customers like NetApp ( NTAP) and Estee Lauder ( EL) distribute and manage their own custom-made mobile apps. "uTest allows us to do more than 90 combinations of different phones, networks, carriers, and versions of the operating system." Companies that release new versions of their app every two weeks or so have roughly 20 to 25 testers on an ongoing basis, while major brands launching a new app covering various geographies and carriers can have up to 300 testers or more, said uTest CEO Doron Reuveni. Other start-ups in the space include Mountain View, Calif.-based Soasta, Perfecto Mobile in Boston and Apica in Sweden.