(at around 1h 30 mins) When the Kims are sneaking out of the house while the Parks are sleeping on the couch, the Kim's are barefoot. When seen running home they somehow now have their shoes. If they had left their shoes at the entrance the Parks would likely have noticed them. It would be more likely they would have left them in the garage.
When three members of the Kim family escape underneath a closing garage door, none of them trip the safety sensor which would reverse the garage door.
The "servant family" gets out with their phones in their pockets and goes to their home completely drenched in rain, then into almost neck-deep water. Yet, despite this, the next morning their phones keep working just fine, as they all receive calls from the rich family on those phones.
After Chung-Sook rushed to cook Ram-don, she dumped her phone into a drawer with all the mess on the table. But when she was slicing sirloin, her phone still remained on the table.
However, this cannot be counted as a continuity goof. Those two shots aren't following each other directly, nor are they meant to be. It's clear that off-screen between those two shots, Chung-Sook completed more steps, such as finding the wooden cutting board, removing the plastic wrapping from the sirloin, *and* retrieving her phone back from the drawer. It's subtle and not explicitly shown, but she is using her phone for reading the instructions of an online Ram-don recipe, which she had been looking up *right before* she rushed into the kitchen (that's why she was bringing the phone into the kitchen in the first place).
However, this cannot be counted as a continuity goof. Those two shots aren't following each other directly, nor are they meant to be. It's clear that off-screen between those two shots, Chung-Sook completed more steps, such as finding the wooden cutting board, removing the plastic wrapping from the sirloin, *and* retrieving her phone back from the drawer. It's subtle and not explicitly shown, but she is using her phone for reading the instructions of an online Ram-don recipe, which she had been looking up *right before* she rushed into the kitchen (that's why she was bringing the phone into the kitchen in the first place).
The pictures on the fridge in the end are definitely not from Germans, but Swiss. The magnets show the Swiss flag, Canton Berne flag and the bridge in Lucerne. However people put fridge magnets up from places they've visited - not usually from where they live! Germans are allowed to enjoy a holiday in Switzerland like anyone else.