criticism Game does not save progress and changes in seed

with so many bugs will end up giving up playing MCPE, please fix these problems soon, it seems that each update appear more bugs and worse. I am unable to play in survival mode, every time the game crashes go out and save the process is changes made in the seed, only the inventory and saved. when I play for a long time in the same seed, the game crashes and exits. when I return to this island changes (dig, put blocks, destroy trees, build things) were not saved completely, and lose the last things done before the game out.