While we are on the subject, if beastmaster ranger(UA version) takes Ape as a companion, could he wield weapons?
I'm thinking of relative simple weapons. clubs, mace, morningstar. no problem with edge alignment.
Also armor?
That's obviously up to the DM. Physically speaking he can wield weapons and wear (custom-made) armor, but he won't be proficient in either.
warhorses wear armor with no problem, so I dont thing it is a stretch to have ape wear hide or similar "simple" armor. Also ape has 6 int that is enough to learn to use tools.