According to BGR, Pokémon Go players have been complaining in their droves on Twitter, Facebook, Reddit, and elsewhere, about a strange bug that has made the game unplayable for some. Apparently, for certain unlucky players, while the game loads up OK and initially looks fine, it soon transpires that all the PokéStops are missing, and there are no Gyms, or, indeed, Pokémon, to be seen anywhere on the map.
The bug only seems to be affecting certain countries, and may have an unusual cause, if Niantic’s tweet to one Trainer is anything to go by, as they asked him, “Which starter Pokémon did you choose in Pokémon Go?” Could this mean that it’s all Squirtle’s, Charmander’s, or Bulbasaur’s fault?! Niantic gave no further clues as to why this might have been causing the bug, but they did also issue another small update to the game today, so hopefully this will have fixed the problem. If not, BGR suggests a fix that has been working for some. All you have to do is go to Settings, and then cellular settings, then disable 4G/LTE and restart your device. When your device reboots, start the game and hopefully all your missing Pokémon, PokémonStops and Gyms should have returned.
Source: How to fix the bug in the latest Pokemon Go update that’s driving players insane