Hangers and related tools which actuate without fluid or mechanical communication between the interior of the tool and its exterior are disclosed. Devices as disclosed herein may include a piston for applying actuating force based on the fluid pressure outside of the tool. The piston may be fixed to a tubing wall or other body of the tool with a shear element to prevent the tool from actuating until a certain pressure is applied to piston, such as by the static pressure of wellbore fluid at a certain depth, by pressure applied to the annulus from surface, or a combination thereof. Actuation of the tool may cause latches to expand outwardly to engage a latch receptacle fixed in or along the host tubing or such actuation may lead to other hanging members, such as slips, to engage the host tubing wall in order to suspend the hanging string therein.