'Love Island' Timmy Pandolfi Says He, Zeta Morrison Doing Great After Win

"Love Island USA" star Timmy Pandolfi is still reelin' from his reality show win ... and says his relationship with Zeta Morrison is still going strong long after the season ended ... and he says keeping things real was a key to their success.

We got the personal trainer leaving Equinox in L.A. Friday ... telling us he's got no complaints from his time on the dating competition series ... and filling us in on how things are goin' with his boo, Zeta.

As for their big W, TP says it's all about being who they really are on camera ... noting the growth of their "pure relationship" had a lot to do with the absence of social media and dating apps.

Fans of the show know Timmy and Zeta were Day 1's on the latest season ... with the cast often referring to them as the "mom and dad" of the group. The 2 stayed strong and went home with $100K in the end -- and, of course, each other.