There are three text messaging apps that come already installed on this device:
Messages (default app)
To switch messaging apps:
From a Home screen, navigate: Apps > Settings.
From the Wireless & networks section, tap More.
Tap Default messaging app then select one of the following:
Alernatively, if prompted, the default messaging app can be changed within the app itself by tapping Set... as your default messaging app (located at the top).