Is it possible to make guacamole without acid? All guacamole recipes call for lime juice, some tomato variant, even hot sauce. I want to make a low-acid guacamole. 

Is the acid necessary? How do I go about making low-acid guacamole? If it plays a role in the finished product, is there something I can substitute?
At its simplest, guacamole is just mashed avocado. Avocado is not particularly acidic on its own, so add whatever non-acidic ingredients you like. 

Consider cilantro, sour cream or whatever low or non-acid flavorings suit you.

See: Browning Avocados - What Helps? for more on acid and avocados.