I'm getting a message in the notification area "Low on Application space". I was installing an .apk from Dropbox and when I touch Install I get an error "Insufficient Application Storage" and an option to Manage Applications or Cancel. I went to the App store and was able to install one via Amazon. I tried again with side-loading and I still get the same errors.
Anyone know what I can do about this?
I have 144 apps (all are very important apps that I MUST have

). My device shows 4.39g of 6.54 available. Seems that should be plenty of space for my little 70 kb app I want to install.