One of the limits of GNSS is in its use in the oceans and other bodies of water. While it can serve some ocean surface applications, its use for tracking marine life that rarely surfaces is limited. However, if we can understand how far underwater GNSS may be received, we can further extend its use envelope and perhaps enable it to serve more marine tracking applications. This paper examines the limits of GNSS reception underwater with measurements data from a smartphone as well as theoretical modeling. Different types of water (tap, distilled and salt) are examined as they have different electrical properties which affects the attenuation of the GNSS signals. The paper also examines the difference in smartphones L1 and L5 reception both on land and underwater.