SJQS is described as 'PDF takeoff and measurement software for quantity surveyors, estimators, and contractors. Measure linear lengths, areas, and volumes directly from PDF construction plans. Organise by trade, calibrate to any scale, and export to Excel or PDF in one click' and is an app. There are more than 10 alternatives to SJQS for Web-based, Windows, SaaS, Mac and iPad. The best SJQS alternative is Bluebeam Revu. It's not free, so if you're looking for a free alternative, you could try Calcufloor or STACK Construction Technologies. Other great apps like SJQS are PriMus-TO, Easy Takeoffs, Buildprax and Precision Plan Pro.