Previously I profiled a company called Twodecode. They recently completed the development thier beta phone client in Symbian C++. Their earlier development with J2ME clients was stopped due to terrible J2ME-support for high-res scans. They are working on a couple of ideas to circumvent this issue; however, additional development under Java/J2ME has received a lower priority.
They are eating their own dog feed and are tracking their own time use with the phone client and codes in the office. They have completed over 300 test scans of different codes (size 1.5 inch x 1.5 inch) on a number of different phones and about 90% of all scans have been successful. Strangly they have found problems in recognizing the codes when the code is printed on high gloss materials or when dark shadows are displayed in the image (mostly shadow of the user standing in front of the code). Nightmare!
They have completed the development of a "pilot" site in Ruby on Rails, with limited functionality, that is going to be used to showcase to potential users and/or partners. They have not (yet) included features for detailed time tracking, budgeted vs worked hours, pay roll export to pay roll service providers etc. But in true Web 2.0 fashion they already have three cleaning/maintenance companies using the basic application in pilot field trials.