Agreed. I'm learning Chinese and while apps are lovely, nothing will prepare you for the pure amount of variation in accents across the world. Real world immersion becomes important for your brain to get used to mapping certain sounds to certain words.

I've also realised it's same for English, except we don't really think about it since we're used to the sounds, but the way we'd say "I went to the market" in daily speech is night and day to how it would be enunciated during an English speaking class (e.g. uh wen tu-th markt vs eye weynt too thee marr-ket). To the unpracticed ear they can just sound like different sentences.