This week I saw an app request for a virtual receipt booklet on one of the Android Forums and I thought "Hm, I wonder how hard that would be to do?" The post pointed out that there are a lot of apps that let you take pictures of physical receipts, but what he wanted was a template that was editable, and more importantly, that the recipient of funds could sign with their finger. I started out trying to figure out how to accomplish that last bit, and ended up cranking out the app in just a few hours. Here's a screen shot:
The app lets you edit any field enclosed in a box just by tapping on the field, then typing a new value. The signature field is signable with your finger. Menu options let you save the receipt as a .jpg to your SD card and/or email it as an attachment to an email straight from the app. So you can write out a receipt virtually, have someone sign it on your device, and immediately email it to yourself and the recipient with a click.
If you have an Android device and need to write receipts on the fly, check it out.