Agreed, this little guy has been through the wars. We need to hop into action.

Louis has it right on, although some plants would reduce stress for the little guy, and a lid so you don't have a frog escapee once he's healed.

You can either buy an amphibian/reptile water conditioner, or Reverse osmosis water for the 1/10 unflavored pedialyte - 9/10 dechlorinated water soak. Regular tap water, if untreated, may kill him.

For this, like Louis said, he'll need a trip to the Exotic Vet ASAP.

I would suggest feeding him some earthworms, either store-bought or from a pesticide/fertilizer/additive free compost/garden. They're so much more nutritious than crickets, and easier to digest too. You can chop them into smaller chunks (ugh, I know) if he can't eat the full worm.

Fingers crossed for the little guy.