DTR Clock is a simple Android mobile app that calculates the date shipped and received codes used on advanced Transportation Control and Movement Documents as specified in USTRANSCOM Defense Transportation Regulation (DTR) - Part II (Cargo Movement) Appendix RR (Date Shipped and Received Codes) dated May 2014 which can be downloaded from http://www.ustranscom.mil/dtr/part-ii/dtr_part_ii_app_rr.pdf.