there are 3 major problems in this game.

problem 1.
As you know, while attacking game, you may touch screen instead of 'end battle' or 'next', and the battle starts, and you must surrender and lose your 1 troop(It may be important unit like dragon, pekka, golem, etc) and trophys.
so, supercell must make a button like 'start battle'(sorry to trophy-pushing down users)

problem 2.
playing game, you may touch upgrade button, purchase gems, purchase shield by mistake.
this is annoying problem for both supercell and coc users.
coc users request these things to supercell and some people fail to redund them.
so, there must be another session like giving 1 minuit to think and do upgrade(purchase things)

problem 3.
there are so much secrets in this game!!!!
did you noticed that lab is still working in a 1/8 speed while upgrading?
did you know that traps can be eliminated by light spell?
supercell is hiding a lot of good things.
why they are hiding these? they must open these things.