Mendeley - Easily organize your papers, read & annotate your PDFs, collaborate in private or open groups, and securely access your research from everywhere.
QuickMark - QuickMark makes everything possible.
Qiqqa - Qiqqa is a free research and reference management software. It can be used in many organizational projects from the academic to the personal to the business endeavor. Read more about Qiqqa.
ZXing - Barcode Scanner for Android
Tax990 - Tax 990 is an IRS-authorized e-filing solution for nonprofit organizations that helps clients understand the process of filing 990 series returns.
Barcode & QR Code Scanner - A free app which allow to read and generate barcodes for Android.