Inside an isolated uniform thin spherical shell :

The gravitational field inside a uniform spherical shell is 0 from gauss law for
gravitation since no mass is enclosed in any Gaussian surface. Since gravitational potential is given by

$\phi =-\int \mathrm{gdr}\text{, hence }\phi =\text{constant since }\mathrm{g}=0$

Since gravitational field is o everywhere, it is apparently same everywhere.