Okular - Okular is a universal document viewer based developed by KDE.
Procore - Procore is the world's most widely used construction project management software. Easy to use, mobile platform with unlimited user licenses.
Sumatra PDF - Sumatra PDF is a slim PDF/DjVu/EPUB/XPS/CHM/CBR/CBZ/MOBI viewer for Windows.
PlanGrid - The #1 construction app. Used by thousands of companies to save time, money, and ditch paper plans forever.
Foxit Reader - Foxit Reader is a free and light-weight multi-platform PDF document viewer.
Corecon - Corecon offers integrated estimating, project management, and job costing for small to medium-sized construction companies.