Lag Problems

Its A Great Game But Can You Get Rid Of The Lag That Happens When You Join A World And When You Log Into Minecraft And Also When You Have To Many World And When Your Trying To Make New Worlds. The Lag Is Really Annoying!

Next I Wanna Say There Is A Problem In The New Update Today I Was Logging In And In A Creative World When I Wad Looking In My Creative Inventory There Was Nothing I Cant Even Use Commands To Get The Blocks Needed!

PhantomEntity about Minecraft: Pocket Edition, v1.1.4