Via Core77: MagicMeasure and MagicPlan by Sensopia are apps that can closely approximate architectural measurements in the field via live interface.  For anyone out there conducting lighting audits or preparing for renovation projects…

MagicPlan is the leading inside mapping technology on mobile devices running iOS and Android. MagicPlan automates the capture of room measurement, shape, and documentation – creating a comprehensive floor plan and a map of any indoor space.