We are busy working on an iphone app in 3 weeks and then an android app in a month. Its the most requested feature so your wife is absolutely right that some people may not want to walk to a comp to enter this stuff. The plan is to then integrate with a company like "red laser" so you can just scan the stuff into your inventory. That would be cool!
It would be cool to somehow use a digital scale to track supplies. Each time you weigh a reagent, the scale could enter the amount used into Quartzy.
Come to think of it, using NFC might work really well for logging supplies. Stick a NFC sticker (I bet tagstand would hook you up) on items you want to track.
Be careful to get it right, most inventory control systems in the real world depend a lot on regular manual updating. Department managers at Walmart, for example, spend an hour or more every morning updating their "automatic" inventory control system manually. Most labs, however, don't have the manpower to spend a lot of time keeping an inventory up to date, so if your system doesn't do a good job, they will just keep using the current "intermittent updating" system.