Rooted Androids

[Ronin]

There is no way to increase your cache, other than to buy a new phone.

Your best bet would be to move more apps to your SD card and hope it will install. If that doesn't work you're out of luck.

Actually there is, within limits.

Basically you need to either modify your partition table manually, or you need to find a rom that does it for you in the setup-process.
If you have a device where small cache is a problem, you will probably find one that does that.

However; Why don't you start out by posting what phone you actually have?