I was thrilled to have a way to watch my usage and it was going great. It was extremely close as far as accuracy until I got to about 70% of my monthly plan. Then it showed I only used 179 MB. Ill give it another billing month to make sure it wasnt anything I did, but if it does it again, Ill be deleting it.
Suededvelvet about Data Master - Monitor Cellular & Wifi Data Usage