Isekai wa Smartphone tomo ni is what happens when anime directors just give up entirely. As Amano Keita from Gamers! said, you can try your best to please everyone and include depth in what you make, or you can just throw a bunch of cliches together and make something that's incredibly fun. This is the latter. There is no merit to its plot, depth of character, and even the main character knows that he is way too OP. His harem doesn't even bother hiding their lack of surprise when something incredible happens. There is no struggle. More than an isekai series, this is slice of life.
In all, this is incredibly fun to watch, especially if you have gone through a lot of other animes and you know all the stereotypes that exist in anime. Nothing phenomenal, and I'm surprised it even got funded. But I would say that's sort of its charm. This is not unlike cult-gathering films such as Napoleon Dynamite in how exaggerated the stereotypes are, and much like Napoleon Dynamite, I'm pretty sure this series won't be forgotten anytime soon.
