There are two kind of solutions. One is to repartition, as you don't mentioned what kind of Android powered Smartphone you have I will try to get deep and the other to move apps to microSD (please read below).
If your device has a MediaTek cpu you can try Meteos Tool for repartitioning, you can find some details here http://www.modaco.com/topic/365701-re-partition-any-mtk6589-phone-without-a-pc-more-data-storage/. This application can be used on the smartphone and repartition the memory to different sizes depending on the selection of the user and the limit of the memory itself. I have used it, it's very easy to be implemented.
The other solution is to use something that is called Link2SD. This although is not repartitioning the memory, it moves every app even other files to the microSD memory (there are solution to run the whole ROM from the microSD) and have free space at the smartphone memory. This way it solves the problem of the internal low memory.
