Confuse check this out

No they made mistake, the Evo V has 1 GB

But there are Evo 3Ds that do have 1,2, and 4 GB I believe

 

That also includes the storage for the OS, not just the app storage. So it's is 4GB but you really have 1 available.

 

There is 4GB of storage but only 1 is free for installing apps, the rest is taken by android, sense, system apps, cache and dalvik cache etc

 

It has 4GB of space. But we are only available to 1, the other 3 are for HTC updates and things like that. So we only have 1 unoccupied gigaByte while the other 3 are reserved for special (HTC) use

 

I recall reading on a forum (perhaps devils toast) that because the sense ui is gone for aosp there is more space that could be potentially accessed. Someone was going to look into it, not sure what the outcome was. .

 

You would have to redo partitions, change permissions etc. It would break the ability to flash other roms. It's really not worth it when you can just pop in a bigger sd card.

You really don't want to screw with the partitions, very easy way to brick your phone.