It depends how you are using this GPL library. If you are calling functions from this library in your code, then in general the GPL would apply to the calling code and therefore your calling code would be subject to the GPL terms, including source code redistribution per this answer:
For Copyleft licenses, how (proprietary- or non-Copyleft- licensed) programs and Copyleft-licensed programs are used together, how they depend and interact with each other is the essence of what triggers the Copyleft clauses of the GPL and LGPL.
If you are instead running this as an independent unmodified tool such as a command line that would be spawned in its own process (I am not sure this is possible on Android FWIW), then you may be using the program (as oppsoed to be based on the program) and only doing a side-by-side redistribution: the GPL would apply to the GPL-licensed library and may not extend to your code.