Purpose: This study aimed to investigate the agreement and test-retest repeatability of two methods for measuring magnitude of toric lens rotation. The two methods assessed were using the slit lamp biomicroscope and a newly developed software tool for the iPhone platform called “Toric App” which uses the built-in camera of the iPhone. Methods: Thirty three participants (66 eyes) wore toric lens (silicon hydrogel material with the prism ballast design) both eyes. Two operators, both registered optometrists, measured toric lens rotation using the two methods. One operator used the same method twice for an assessment of test-retest repeatability of each method. Inter- and intra-operator agreement and repeatability were assessed using Bland-Altman analysis. Results: The ninety-five percent confidence intervals (95% CIs) for the limits of agreement between the silt-lamp biomicroscope and Toric App methods was ±9.1 degrees. Measurements using the two different methods showed no statistically significant mean difference (0.40) (paired t-test, p=0.32). Inter-observer agreement of lens rotation was ±7.9 degree (95% CIs) using the slit-lamp microscope and ±7.8 degree using the Toric App. Intra-observer repeatability was ±6.6 degree using the slit lamp microscope and ±6.8 using the Toric App. Conclusions: The results should be considered in view of the fact that toric lenses are not static but move with the blink thus the location of the reference point is unlikely to be at exactly the same location at the different measurement times. Despite this source of variability in the results, the newly developed software tool for iPhone provides clinically comparable performance to slit lamp biomicroscope measurement which does not appear to be operator dependent. This software tool may be a useful for those optometric practices have limited access to a slit-lamp biomicroscop