Unfortunately, I found this to be true as well. I was learning French and to practice I began saying little phrases to my Haitian Creole speaking friend. He has a solid grasp on French as well or at least enough to raise an eyebrow at some phrases I was saying. He said it was close but not quite right. Of course, I figured he just didn't know French as well as creole until the one phrase I did recognize was just inaccurate. I stopped using the app after that for fear that I would waste my time learning a lot of correct vocabulary with so-so (if not awful) grammar.
Hola! Yo quiero aprender Español porque mi padre es Puertorriqueño. Cuando yo era niña, yo vivía con mi madre quién es Americana-Africana así que no hablo Español. Quiero una conexion con ambas culturas. Ademas, yo vivo en Nueva York con muchas personas quienes hablar Español!