The texture for dispensers and droppers in the hotbar, and survival/creative inventory have a vertical face instead of the horizontal face. Also, the dispensers and droppers when dropped have both the vertical/horizontal textures on two faces of the block.
Thanks for your report! This is however a Duplicate of MCPE-14635 – If you have not, please use the search function in the future, to see if your bug has already been submitted, as currently over 47% of tickets are being closed as duplicate.