Illuminance measurement traditionally relies on luxmeters. Smartphone users are increasing exponentially due to its capabilities and cost. Embedded sensors and available mobile applications (apps) turn it into a potential illuminance measuring equipment. This study assessed the performance of a set of 11 smartphones and 6 apps used to measure illuminance levels provided by 3 LED lamps with different correlated color temperature (2700, 4000, and 6500 K) and at different distances from the light fixture. The obtained results were compared to those of a calibrated luxmeter. iOS-based equipment tends to underestimate illuminance levels whereas the Android ones tend to do the opposite. Only 2.3% of the illuminance measurements based on iOS combinations were accurate with 90.2% of the measurements differing less than 100% from the reference values. Nearly all measurements (98.3%) performed with Android combinations differed more than 100% from the luxmeter measures. No performance pattern was identified among the tested equipment. These results are in accordance with previous studies despite referring to more modern equipment. Smartphones still do not ensure the necessary accuracy level when measuring illuminance.