CHARCOAL LIGHTER FLUID
Not sure if this will work for iPads but I use it for laptop digitizer bezels and it works for me.
Pour some lighter fluid into a small glass. Not much, just enough to dip a Q-tip.
Dip the Q-tip into the fluid and gently coat the adhesive and let it soak in for a few minutes.
Use the dipped Q-tip to remove the adhesive using a forward pushing motion as if you are shoveling or chiseling it off. It softens the adhesive to a point which it won't stick to your fingers and leaves no residue. There may be an oily feel and doesn't smell too great but it works pretty good actually.
After completely removing the adhesive, I go back around the bezel and clean with rubbing alcohol to remove and residual finger prints, adhesive debris, etc.
Oh and I don't recommend smoking while handling the lighter fluid and would recommend not using it around any electrical sources or batteries, etc.